Remove check for SPI_GETKEYBOARDCUES.

<https://msdn.microsoft.com/en-us/library/windows/desktop/ms724947(v=vs.85).aspx>

src/msw/menuitem.cpp

@@ -143,10 +143,6 @@ inline bool IsGreaterThanStdSize(const wxBitmap& bmp)
 #include "wx/fontutil.h"
 #include "wx/msw/private/metrics.h"
 
-#ifndef SPI_GETKEYBOARDCUES
-#define SPI_GETKEYBOARDCUES 0x100A
-#endif
-
 #if wxUSE_UXTHEME
 
 enum MENUPARTS