f2fs: fix error return code in init_f2fs_fs()

Fix to return -ENOMEM in the kset create and add error handling
case instead of 0, as done elsewhere in this function.

Introduced by commit b59d0bae.
(f2fs: add sysfs support for controlling the gc_thread)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
[Jaegeuk Kim: merge the patch with previous modification]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/super.c

@@ -1012,8 +1012,10 @@ static int __init init_f2fs_fs(void)
 	if (err)
 		goto free_gc_caches;
 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
-	if (!f2fs_kset)
+	if (!f2fs_kset) {
+		err = -ENOMEM;
 		goto free_checkpoint_caches;
+	}
 	err = register_filesystem(&f2fs_fs_type);
 	if (err)
 		goto free_kset;