include: Make stdbool.h a separate file

This patch moves the traditional POSIX stdbool.h definitions out from
stdint.h into their own file. This helps for using these definitions in
commonlib code which may be compiled in different environments. For
coreboot everything should chain-include this stuff via types.h anyway
so nothing should change.

Change-Id: Ic8d52be80b64d8e9564f3aee8975cb25e4c187f5
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36837
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/include/stdbool.h

@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __STDBOOL_H__
+#define __STDBOOL_H__
+
+#include <stdint.h>
+
+#ifdef __ROMCC__
+typedef uint8_t bool;
+#else
+typedef _Bool   bool;
+#endif
+#define true    1
+#define false   0
+
+#endif /* __STDBOOL_H__ */