vfio/mdev: don't warn if ->request is not set

Only a single driver actually sets the ->request method, so don't print
a scary warning if it isn't.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210726143524.155779-3-hch@lst.deSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/mdev/mdev_core.c

@@ -138,10 +138,6 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
 	if (!dev)
 		return -EINVAL;
 
-	/* Not mandatory, but its absence could be a problem */
-	if (!ops->request)
-		dev_info(dev, "Driver cannot be asked to release device\n");
-
 	mutex_lock(&parent_list_lock);
 
 	/* Check for duplicate */