Add facility to reset split mode when closing a rig connection

This option defaults to on but may be unchecked in settings.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6359 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

TransceiverBase.cpp

@@ -52,7 +52,7 @@ void TransceiverBase::start () noexcept
     }
 }
 
-void TransceiverBase::stop () noexcept
+void TransceiverBase::stop (bool reset_split) noexcept
 {
   QString message;
   try
@@ -64,6 +64,12 @@ void TransceiverBase::stop () noexcept
               // try and ensure PTT isn't left set
               do_ptt (false);
               do_post_ptt (false);
+              if (reset_split)
+                {
+                  // try and reset split mode
+                  do_tx_frequency (0, false);
+                  do_post_tx_frequency (0, false);
+                }
             }
           catch (...)
             {