lockdep: Fix missing entry in /proc/lock_stat

One entry is missing in the output of /proc/lock_stat.

The cause is, when ls_start() is called the 2nd time, we should
start from stats[@pos-1] but not stats[@pos], because pos == 0
is the header.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED15.20800@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/lockdep_proc.c

@@ -634,7 +634,7 @@ static void *ls_start(struct seq_file *m, loff_t *pos)
 	if (*pos == 0)
 		return SEQ_START_TOKEN;
 
-	data->iter = data->stats + *pos;
+	data->iter = data->stats + (*pos - 1);
 	if (data->iter >= data->iter_end)
 		data->iter = NULL;