The existing code calls server->ops->close() that is not
right. This causes XFS test generic/310 to fail. Fix this
by using server->ops->closedir() function.

Cc: <stable@vger.kernel.org> # v3.7+
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>