headers: Fix include guard for functiondiscoverykeys_devpkey.h

Signed-off-by: LIU Hao <lh_mouse@126.com>
diff --git a/mingw-w64-headers/include/functiondiscoverykeys_devpkey.h b/mingw-w64-headers/include/functiondiscoverykeys_devpkey.h
index 49e739f..47e0645 100644
--- a/mingw-w64-headers/include/functiondiscoverykeys_devpkey.h
+++ b/mingw-w64-headers/include/functiondiscoverykeys_devpkey.h
@@ -3,8 +3,8 @@
  * This file is part of the mingw-w64 runtime package.
  * No warranty is given; refer to the file DISCLAIMER.PD within this package.
  */
-#ifndef _INC_FUNCTIONDISCOVERYKEYS
-#define _INC_FUNCTIONDISCOVERYKEYS
+#ifndef _INC_FUNCTIONDISCOVERYKEYS_DEVPKEY
+#define _INC_FUNCTIONDISCOVERYKEYS_DEVPKEY
 
 #include <propkeydef.h>