simplewallet: deduplicate human-readable timespan function

diff --git a/src/common/util.h b/src/common/util.h
index 821ad70..3b0f1db 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -275,6 +275,11 @@ namespace tools
 
   std::string get_human_readable_timespan(uint64_t seconds);
 
+  inline std::string get_human_readable_timespan(std::chrono::seconds seconds)
+  {
+    return get_human_readable_timespan(static_cast<uint64_t>(seconds.count()));
+  }
+
   std::string get_human_readable_bytes(uint64_t bytes);
 
   void clear_screen();
diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index 50c61d4..658613a 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -162,9 +162,6 @@ using tools::fee_priority;
     } \
   } while (0)
 
-static std::string get_human_readable_timespan(std::chrono::seconds seconds);
-static std::string get_human_readable_timespan(uint64_t seconds);
-
 namespace
 {
   constexpr std::array<std::string_view, 5> allowed_priority_strings = tools::fee_priority_utilities::fee_priority_strings;
@@ -2251,7 +2248,7 @@ bool simple_wallet::public_nodes(const std::vector<std::string> &args)
     message_writer() << boost::format("%32s %16s") % tr("address") % tr("last_seen");
     for (const auto &node: nodes)
     {
-      const std::string last_seen = node.last_seen == 0 ? tr("never") : get_human_readable_timespan(std::chrono::seconds(now - node.last_seen));
+      const std::string last_seen = node.last_seen == 0 ? tr("never") : tools::get_human_readable_timespan(std::chrono::seconds(now - node.last_seen));
       std::string host = node.host + ":" + std::to_string(node.rpc_port);
       message_writer() << boost::format("%32s %16s") % host % last_seen;
     }
@@ -5852,11 +5849,11 @@ bool simple_wallet::show_balance_unlocked(bool detailed)
   uint64_t unlocked_balance = m_wallet->unlocked_balance(m_current_subaddress_account, false, &blocks_to_unlock, &time_to_unlock);
   std::string unlock_time_message;
   if (blocks_to_unlock > 0 && time_to_unlock > 0)
-    unlock_time_message = (boost::format(" (%lu block(s) and %s to unlock)") % blocks_to_unlock % get_human_readable_timespan(time_to_unlock)).str();
+    unlock_time_message = (boost::format(" (%lu block(s) and %s to unlock)") % blocks_to_unlock % tools::get_human_readable_timespan(time_to_unlock)).str();
   else if (blocks_to_unlock > 0)
     unlock_time_message = (boost::format(" (%lu block(s) to unlock)") % blocks_to_unlock).str();
   else if (time_to_unlock > 0)
-    unlock_time_message = (boost::format(" (%s to unlock)") % get_human_readable_timespan(time_to_unlock)).str();
+    unlock_time_message = (boost::format(" (%s to unlock)") % tools::get_human_readable_timespan(time_to_unlock)).str();
   success_msg_writer() << tr("Balance: ") << print_money(m_wallet->balance(m_current_subaddress_account, false)) << ", "
     << tr("unlocked balance: ") << print_money(unlocked_balance) << unlock_time_message << extra;
   std::map<uint32_t, uint64_t> balance_per_subaddress = m_wallet->balance_per_subaddress(m_current_subaddress_account, false);
@@ -8385,27 +8382,6 @@ bool simple_wallet::check_reserve_proof(const std::vector<std::string> &args)
   return true;
 }
 //----------------------------------------------------------------------------------------------------
-static std::string get_human_readable_timespan(std::chrono::seconds seconds)
-{
-  uint64_t ts = seconds.count();
-  if (ts < 60)
-    return std::to_string(ts) + sw::tr(" seconds");
-  if (ts < 3600)
-    return std::to_string((uint64_t)(ts / 60)) + sw::tr(" minutes");
-  if (ts < 3600 * 24)
-    return std::to_string((uint64_t)(ts / 3600)) + sw::tr(" hours");
-  if (ts < 3600 * 24 * 30.5)
-    return std::to_string((uint64_t)(ts / (3600 * 24))) + sw::tr(" days");
-  if (ts < 3600 * 24 * 365.25)
-    return std::to_string((uint64_t)(ts / (3600 * 24 * 30.5))) + sw::tr(" months");
-  return sw::tr("a long time");
-}
-//----------------------------------------------------------------------------------------------------
-static std::string get_human_readable_timespan(uint64_t seconds)
-{
-  return get_human_readable_timespan(std::chrono::seconds(seconds));
-}
-//----------------------------------------------------------------------------------------------------
 // mutates local_args as it parses and consumes arguments
 bool simple_wallet::get_transfers(std::vector<std::string>& local_args, std::vector<transfer_view>& transfers)
 {
@@ -8514,7 +8490,7 @@ bool simple_wallet::get_transfers(std::vector<std::string>& local_args, std::vec
           const uint64_t adjusted_time = m_wallet->get_daemon_adjusted_time();
           uint64_t threshold = adjusted_time + (m_wallet->use_fork_rules(2, 0) ? CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_SECONDS_V2 : CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_SECONDS_V1);
           if (threshold < pd.m_unlock_time)
-            locked_msg = get_human_readable_timespan(std::chrono::seconds(pd.m_unlock_time - threshold));
+            locked_msg = tools::get_human_readable_timespan(std::chrono::seconds(pd.m_unlock_time - threshold));
         }
       }
       transfers.push_back({
@@ -10259,9 +10235,9 @@ bool simple_wallet::show_transfer(const std::vector<std::string> &args)
         const uint64_t adjusted_time = m_wallet->get_daemon_adjusted_time();
         uint64_t threshold = adjusted_time + (m_wallet->use_fork_rules(2, 0) ? CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_SECONDS_V2 : CRYPTONOTE_LOCKED_TX_ALLOWED_DELTA_SECONDS_V1);
         if (threshold >= pd.m_unlock_time)
-          success_msg_writer() << "unlocked for " << get_human_readable_timespan(std::chrono::seconds(threshold - pd.m_unlock_time));
+          success_msg_writer() << "unlocked for " << tools::get_human_readable_timespan(std::chrono::seconds(threshold - pd.m_unlock_time));
         else
-          success_msg_writer() << "locked for " << get_human_readable_timespan(std::chrono::seconds(pd.m_unlock_time - threshold));
+          success_msg_writer() << "locked for " << tools::get_human_readable_timespan(std::chrono::seconds(pd.m_unlock_time - threshold));
       }
       success_msg_writer() << "Address index: " << pd.m_subaddr_index.minor;
       success_msg_writer() << "Note: " << m_wallet->get_tx_note(txid);
@@ -10637,7 +10613,7 @@ void simple_wallet::list_mms_messages(const std::vector<mms::message> &messages)
             m.wallet_height %
             m.round %
             ms.message_state_to_string(m.state) %
-            (tools::get_human_readable_timestamp(m.modified) + ", " + get_human_readable_timespan(std::chrono::seconds(now - m.modified)) + tr(" ago"));
+            (tools::get_human_readable_timestamp(m.modified) + ", " + tools::get_human_readable_timespan(std::chrono::seconds(now - m.modified)) + tr(" ago"));
   }
 }
 
@@ -10703,7 +10679,7 @@ void simple_wallet::show_message(const mms::message &m)
   message_writer() << tr("In/out: ") << ms.message_direction_to_string(m.direction);
   message_writer() << tr("Type: ") << ms.message_type_to_string(m.type);
   message_writer() << tr("State: ") << boost::format(tr("%s since %s, %s ago")) %
-          ms.message_state_to_string(m.state) % tools::get_human_readable_timestamp(m.modified) % get_human_readable_timespan(std::chrono::seconds(now - m.modified));
+          ms.message_state_to_string(m.state) % tools::get_human_readable_timestamp(m.modified) % tools::get_human_readable_timespan(std::chrono::seconds(now - m.modified));
   if (m.sent == 0)
   {
     message_writer() << tr("Sent: Never");
@@ -10711,7 +10687,7 @@ void simple_wallet::show_message(const mms::message &m)
   else
   {
     message_writer() << boost::format(tr("Sent: %s, %s ago")) %
-            tools::get_human_readable_timestamp(m.sent) % get_human_readable_timespan(std::chrono::seconds(now - m.sent));
+            tools::get_human_readable_timestamp(m.sent) % tools::get_human_readable_timespan(std::chrono::seconds(now - m.sent));
   }
   message_writer() << tr("Authorized signer: ") << ms.signer_to_string(signer, 100);
   message_writer() << tr("Content size: ") << m.content.length() << tr(" bytes");