Removed #include of wingdi.h and windef.h from winuser.h (and resolved
the resulting compilation failures).

diff --git a/msdos/int33.c b/msdos/int33.c
index e78f78b..6c6dbf0 100644
--- a/msdos/int33.c
+++ b/msdos/int33.c
@@ -3,6 +3,8 @@
  */
 
 #include <stdlib.h>
+#include "windef.h"
+#include "wingdi.h"
 #include "winuser.h"
 #include "miscemu.h"
 #include "dosexe.h"