MacOSX: compile error fix after r3329

include/class_drawpanel.h

@@ -33,7 +33,6 @@
 
 #include "colors.h"
 #include "base_struct.h"
-#include <wx/overlay.h>
 
 class EDA_DRAW_FRAME;
 class BASE_SCREEN;

include/wxstruct.h

@@ -46,6 +46,10 @@
 #include "colors.h"
 #include "common.h"
 
+#ifdef USE_WX_OVERLAY
+#include <wx/overlay.h>
+#endif
+
 // C++ guarantees that operator delete checks its argument for null-ness
 #ifndef SAFE_DELETE
 #define SAFE_DELETE( p ) delete (p); (p) = NULL;