ecryptfs: use DEFINE_MUTEX() for mutex lock

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

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>

fs/ecryptfs/crypto.c

@@ -1590,11 +1590,10 @@ out:
 
 struct kmem_cache *ecryptfs_key_tfm_cache;
 static struct list_head key_tfm_list;
-struct mutex key_tfm_list_mutex;
+DEFINE_MUTEX(key_tfm_list_mutex);
 
 int __init ecryptfs_init_crypto(void)
 {
-	mutex_init(&key_tfm_list_mutex);
 	INIT_LIST_HEAD(&key_tfm_list);
 	return 0;
 }