tools: Add missing stdio.h include to asm/bug.h header

We have a direct fprintf() call in the header, so we need stdio.h
include, otherwise it could fail compilation if there's no prior stdio.h
include directive.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/n/tip-8hvjgh24olfsa4non0a3ohnq@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>