Ditch it, noone is using it, one more stdio.h include in a hot header.

Fix the fallout in parse-events.y, where we end up using a FILE pointer,
I think due to YYDEBUG being set and in some places, like Amazon Linux 1
we don't get stdio.h included by luck, like in most other places, add a
explicit stdio.h include directive.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-37k5q0lhdbo2hvvfbnnzn7og@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>