ftrace: Fix the output of profile

The first entry of the ftrace profile was always skipped when
reading trace_stat/functionX.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A443D59.4080307@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/trace/ftrace.c

@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
 	pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
 
  again:
-	rec++;
+	if (idx != 0)
+		rec++;
+
 	if ((void *)rec >= (void *)&pg->records[pg->index]) {
 		pg = pg->next;
 		if (!pg)