virtio: hand virtio ring alignment as argument to vring_new_virtqueue

This allows each virtio user to hand in the alignment appropriate to
their virtio_ring structures.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

drivers/s390/kvm/kvm_virtio.c

@@ -193,7 +193,8 @@ static struct virtqueue *kvm_find_vq(struct virtio_device *vdev,
 	if (err)
 		goto out;
 
-	vq = vring_new_virtqueue(config->num, vdev, (void *) config->address,
+	vq = vring_new_virtqueue(config->num, KVM_S390_VIRTIO_RING_ALIGN,
+				 vdev, (void *) config->address,
 				 kvm_notify, callback);
 	if (!vq) {
 		err = -ENOMEM;