f2fs: fix to put root inode in error path of fill_super

We should put root inode correctly in error path of fill_super, otherwise we
may encounter a leak case of inode resource.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/super.c

@@ -1033,8 +1033,9 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 		goto free_node_inode;
 	}
 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
+		iput(root);
 		err = -EINVAL;
-		goto free_root_inode;
+		goto free_node_inode;
 	}
 
 	sb->s_root = d_make_root(root); /* allocate root dentry */