perf top: Fix a memory leak

The 'buf' should be freed when symbol wasn't found too.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325000151-4463-3-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-top.c

@@ -351,7 +351,6 @@ static void perf_top__prompt_symbol(struct perf_top *top, const char *msg)
 	if (!found) {
 		fprintf(stderr, "Sorry, %s is not active.\n", buf);
 		sleep(1);
-		return;
 	} else
 		perf_top__parse_source(top, found);