Btrfs: use the correct type when creating cow dio extent

'BTRFS_ORDERED_REGULAR' was introduced for the cow case in patch
'Btrfs: specify a new ordered extent type for create_io_em',
but it missed the directIO cow case.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>

fs/btrfs/inode.c

@@ -7190,7 +7190,7 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
 
 	em = btrfs_create_dio_extent(inode, start, ins.offset, start,
 				     ins.objectid, ins.offset, ins.offset,
-				     ins.offset, 0);
+				     ins.offset, BTRFS_ORDERED_REGULAR);
 	btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 	if (IS_ERR(em))
 		btrfs_free_reserved_extent(fs_info, ins.objectid,