mac80211: add back lost debugfs files

Somehow these files were never present or lost, but the code
is there and they seem somewhat useful, so add them back.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

path: root/tools/perf/builtin-version.c

#include "util/util.h"
#include "builtin.h"
#include "perf.h"

int cmd_version(int argc __maybe_unused, const char **argv __maybe_unused,
		const char *prefix __maybe_unused)
{
	printf("perf version %s\n", perf_version_string);
	return 0;
}