tools/nolibc: add the more portable inttypes.h

It's often recommended to only use inttypes.h instead of stdint.h for
portability reasons since the former is always present when the latter
is present, but not conversely, and the former includes the latter. Due
to this some simple programs fail to build when including inttypes.h.
Let's add one that simply includes nolibc.h to better support these
programs.

Signed-off-by: Willy Tarreau <[e-mail]>
Signed-off-by: Thomas Weißschuh <[e-mail]>

tools/include/nolibc/Makefile

···
 		errno.h \
 		fcntl.h \
 		getopt.h \
+		inttypes.h \
 		limits.h \
 		math.h \
 		nolibc.h \

tools/include/nolibc/inttypes.h

···
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+
+#include "nolibc.h"