Removed private wxGetLocalTimeUsec() function from Unix code.

The function was badly named as it returned UTC time and not local time and
can be simply replaced with the just added public wxGetUTCTimeUSec().

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@69839 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/unix/private/timer.h

@@ -134,12 +134,6 @@ private:
     static wxTimerScheduler *ms_instance;
 };
 
-// this helper function currently only exists for Unix platforms but could be
-// moved to wx/stopwatch.h if it turns out to be useful elsewhere
-//
-// returns the number of microseconds since the Epoch
-extern wxUsecClock_t wxGetLocalTimeUsec();
-
 #endif // wxUSE_TIMER
 
 #endif // _WX_UNIX_PRIVATE_TIMER_H_