[PATCH -next] bcache: use DEFINE_MUTEX() for mutex lock

[Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>]

mutex lock can be initialized automatically with DEFINE_MUTEX()
rather than explicitly calling mutex_init().

Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>
---
 drivers/md/bcache/super.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 78c08a8aece8..c124da6e646d 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -41,7 +41,7 @@ static const char invalid_uuid[] = {
 };
 
 static struct kobject *bcache_kobj;
-struct mutex bch_register_lock;
+DEFINE_MUTEX(bch_register_lock);
 bool bcache_is_reboot;
 LIST_HEAD(bch_cache_sets);
 static LIST_HEAD(uncached_devices);
@@ -2870,7 +2870,6 @@ static int __init bcache_init(void)
 
 	check_module_parameters();
 
-	mutex_init(&bch_register_lock);
 	init_waitqueue_head(&unregister_wait);
 	register_reboot_notifier(&reboot);