remove unused gtk includes

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@59020 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/wincmn.cpp

@@ -72,16 +72,6 @@
     #include "wx/sysopt.h"
 #endif
 
-// For reporting compile- and runtime version of GTK+ in the ctrl+alt+mclick dialog.
-// The gtk includes don't pull any other headers in, at least not on my system - MR
-#ifdef __WXGTK__
-    #ifdef __WXGTK20__
-        #include <gtk/gtkversion.h>
-    #else
-        #include <gtk/gtkfeatures.h>
-    #endif
-#endif
-
 #include "wx/platinfo.h"
 
 // Windows List