tracing/core: fix early free of cpumasks

Impact: fix crashes when tracing cpumasks

While ring-buffer allocation, the cpumasks are allocated too,
including the tracing cpumask and the per-cpu file mask handler.
But these cpumasks are freed accidentally just after.
Fix it.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1237164303-11476-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/trace/trace.c

@@ -4125,7 +4125,8 @@ __init static int tracer_alloc_buffers(void)
 				       &trace_panic_notifier);
 
 	register_die_notifier(&trace_die_notifier);
-	ret = 0;
+
+	return 0;
 
 out_free_cpumask:
 	free_cpumask_var(tracing_reader_cpumask);