udf: Truncate added extents on failed expansion

commit 70bfb3a8 upstream.

When a file expansion failed because we didn't have enough space for
indirect extents make sure we truncate extents created so far so that we
don't leave extents beyond EOF.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>