Revert "virtio-net: don't let virtio core to validate used length"

This reverts commit 816625c.

Attempts to validate length in the core did not work out.
We'll drop them, so revert the dependent changes in drivers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Author: mstsirkin

drivers/net/virtio_net.c

@@ -3423,7 +3423,6 @@ static struct virtio_driver virtio_net_driver = {
 	.feature_table_size = ARRAY_SIZE(features),
 	.feature_table_legacy = features_legacy,
 	.feature_table_size_legacy = ARRAY_SIZE(features_legacy),
-	.suppress_used_validation = true,
 	.driver.name =	KBUILD_MODNAME,
 	.driver.owner =	THIS_MODULE,
 	.id_table =	id_table,