ubd: remove commented out code in ubd_open

This code has been dead forever, make sure it doesn't show up in code
searches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/r/20230608110258.189493-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

arch/um/drivers/ubd_kern.c

@@ -1170,13 +1170,6 @@ static int ubd_open(struct gendisk *disk, fmode_t mode)
 	}
 	ubd_dev->count++;
 	set_disk_ro(disk, !ubd_dev->openflags.w);
-
-	/* This should no more be needed. And it didn't work anyway to exclude
-	 * read-write remounting of filesystems.*/
-	/*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){
-	        if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev);
-	        err = -EROFS;
-	}*/
 out:
 	mutex_unlock(&ubd_mutex);
 	return err;