f2fs: fix to unlock f2fs_lock at the omitted error case

If it occurs an error, we should call f2fs_unlock_op.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/inline.c

@@ -81,8 +81,10 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
 
 	f2fs_lock_op(sbi);
 	ipage = get_node_page(sbi, inode->i_ino);
-	if (IS_ERR(ipage))
-		return PTR_ERR(ipage);
+	if (IS_ERR(ipage)) {
+		err = PTR_ERR(ipage);
+		goto out;
+	}
 
 	/*
 	 * i_addr[0] is not used for inline data,
@@ -90,10 +92,8 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
 	 */
 	set_new_dnode(&dn, inode, ipage, NULL, 0);
 	err = f2fs_reserve_block(&dn, 0);
-	if (err) {
-		f2fs_unlock_op(sbi);
-		return err;
-	}
+	if (err)
+		goto out;
 
 	zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);
 
@@ -118,6 +118,7 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
 
 	sync_inode_page(&dn);
 	f2fs_put_dnode(&dn);
+out:
 	f2fs_unlock_op(sbi);
 	return err;
 }