cdrom_open() forgets to unlock on -EROFS failure exits

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

drivers/cdrom/cdrom.c

@@ -1032,6 +1032,10 @@ int cdrom_open(struct cdrom_device_info *cdi, struct inode *ip, struct file *fp)
 	check_disk_change(ip->i_bdev);
 	return 0;
 err_release:
+	if (CDROM_CAN(CDC_LOCK) && cdi->options & CDO_LOCK) {
+		cdi->ops->lock_door(cdi, 0);
+		cdinfo(CD_OPEN, "door unlocked.\n");
+	}
 	cdi->ops->release(cdi);
 err:
 	cdi->use_count--;