ubifs: too early register_filesystem()

doing that before you are ready to handle mount() is a Bad Idea(tm)...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/ubifs/super.c

@@ -2264,19 +2264,12 @@ static int __init ubifs_init(void)
 		return -EINVAL;
 	}
 
-	err = register_filesystem(&ubifs_fs_type);
-	if (err) {
-		ubifs_err("cannot register file system, error %d", err);
-		return err;
-	}
-
-	err = -ENOMEM;
 	ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
 				sizeof(struct ubifs_inode), 0,
 				SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
 				&inode_slab_ctor);
 	if (!ubifs_inode_slab)
-		goto out_reg;
+		return -ENOMEM;
 
 	register_shrinker(&ubifs_shrinker_info);
 
@@ -2288,15 +2281,20 @@ static int __init ubifs_init(void)
 	if (err)
 		goto out_compr;
 
+	err = register_filesystem(&ubifs_fs_type);
+	if (err) {
+		ubifs_err("cannot register file system, error %d", err);
+		goto out_dbg;
+	}
 	return 0;
 
+out_dbg:
+	dbg_debugfs_exit();
 out_compr:
 	ubifs_compressors_exit();
 out_shrinker:
 	unregister_shrinker(&ubifs_shrinker_info);
 	kmem_cache_destroy(ubifs_inode_slab);
-out_reg:
-	unregister_filesystem(&ubifs_fs_type);
 	return err;
 }
 /* late_initcall to let compressors initialize first */