Use angle brackets (<>) rather than quotes ("") for the include
directives in our .h files. This should avoid some potentially nasty
surprises for Winelib apps.

diff --git a/include/dinput.h b/include/dinput.h
index c62329a..e056b4f 100644
--- a/include/dinput.h
+++ b/include/dinput.h
@@ -19,8 +19,8 @@
 #ifndef __WINE_DINPUT_H
 #define __WINE_DINPUT_H
 
-#include "windef.h" /* for MAX_PATH */
-#include "objbase.h"
+#include <windef.h> /* for MAX_PATH */
+#include <objbase.h>
 
 #ifndef DIRECTINPUT_VERSION
 #define DIRECTINPUT_VERSION	0x0800