cred: Use KMEM_CACHE() instead of kmem_cache_create()

Commit 0a31bd5f ("KMEM_CACHE(): simplify slab cache creation")
introduces a new macro. Use the new KMEM_CACHE() macro instead of
direct kmem_cache_create() to simplify the creation of SLAB caches.
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
[PM: alignment fixes in both code and description]
Signed-off-by: Paul Moore <paul@paul-moore.com>

kernel/cred.c

@@ -606,8 +606,8 @@ int set_cred_ucounts(struct cred *new)
 void __init cred_init(void)
 {
 	/* allocate a slab in which we can store credentials */
-	cred_jar = kmem_cache_create("cred_jar", sizeof(struct cred), 0,
-			SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, NULL);
+	cred_jar = KMEM_CACHE(cred,
+			      SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT);
 }
 
 /**