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

diff --git a/windows/driver.c b/windows/driver.c
index aee0e9d..0899be7 100644
--- a/windows/driver.c
+++ b/windows/driver.c
@@ -10,6 +10,8 @@
 
 #include <string.h>
 #include "heap.h"
+#include "windef.h"
+#include "wingdi.h"
 #include "winuser.h"
 #include "driver.h"
 #include "ldt.h"