perf tools: Fix leaking rec_argv in error cases

Let's free the allocated rec_argv in case we return early, in order to
avoid leaking memory.

This adds free() at a few very similar places across the tree where it
was missing.

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Martin kepplinger <martink@posteo.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170913191419.29806-1-martink@posteo.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-c2c.c

@@ -2732,6 +2732,7 @@ static int perf_c2c__record(int argc, const char **argv)
 		if (!perf_mem_events[j].supported) {
 			pr_err("failed: event '%s' not supported\n",
 			       perf_mem_events[j].name);
+			free(rec_argv);
 			return -1;
 		}