Revert "perf tools: Improve setting of gcc debug option"

This reverts commit e8b7ea43

.

Martin created a gcc PR:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68836

Reported-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin Liska <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>,
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20151202164827.GA21124@krava.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>