[SDK][CRT] Correct stdbool.h and remove an unused one

sdk/include/crt/mingw32/stdbool.h

@@ -1,53 +0,0 @@
-/* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
-
-This file is part of GCC.
-
-GCC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-GCC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING.  If not, write to
-the Free Software Foundation, 51 Franklin Street, Fifth Floor,
-Boston, MA 02110-1301, USA.  */
-
-/* As a special exception, if you include this header file into source
-   files compiled by GCC, this header file does not by itself cause
-   the resulting executable to be covered by the GNU General Public
-   License.  This exception does not however invalidate any other
-   reasons why the executable file might be covered by the GNU General
-   Public License.  */
-
-/*
- * ISO C Standard:  7.16  Boolean type and values  <stdbool.h>
- */
-
-#ifndef _STDBOOL_H
-#define _STDBOOL_H
-
-#ifndef __cplusplus
-
-#define bool	_Bool
-#define true	1
-#define false	0
-
-#else /* __cplusplus */
-
-/* Supporting <stdbool.h> in C++ is a GCC extension.  */
-#define _Bool	bool
-#define bool	bool
-#define false	false
-#define true	true
-
-#endif /* __cplusplus */
-
-/* Signal that all the definitions are present.  */
-#define __bool_true_false_are_defined	1
-
-#endif	/* stdbool.h */

sdk/include/crt/stdbool.h

@@ -28,7 +28,7 @@
 
 /* Don't define bool, true, and false in C++, except as a GNU extension. */
 #ifndef __cplusplus
-#if _MSC_VER <= 1600
+#if defined(_MSC_VER) && _MSC_VER <= 1600
 #define bool unsigned char
 #else
 #define bool _Bool