Fix wxQT monolithic build on Linux

- Remove duplicate wxConsoleAppTraits::CreateEventLoop()
  It's already defined for Unix as well as Windows

- Remove wxEventLoop AddSourceForFD() "override"
  the base version is static and therefore clearly not meant to be overridden

include/wx/qt/evtloop.h

@@ -27,10 +27,6 @@ public:
 
     void ScheduleIdleCheck();
 
-#if wxUSE_EVENTLOOP_SOURCE
-    virtual wxEventLoopSource *AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags);
-#endif // wxUSE_EVENTLOOP_SOURCE
-
 private:
     QEventLoop *m_qtEventLoop;
     wxObjectDataPtr<wxQtIdleTimer> m_qtIdleTimer;