vhost: fix virtqueue use after free on NUMA reallocation

translate_ring_addresses (via numa_realloc) may change a virtio device and
virtio queue.
The virtqueue object must be refreshed before accessing the lock.

Fixes: 04c27cb ("vhost: fix unsafe vring addresses modifications")
Cc: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

lib/vhost/vhost_user.c

@@ -2596,6 +2596,7 @@ vhost_user_iotlb_msg(struct virtio_net **pdev,
 			if (is_vring_iotlb(dev, vq, imsg)) {
 				rte_spinlock_lock(&vq->access_lock);
 				*pdev = dev = translate_ring_addresses(dev, i);
+				vq = dev->virtqueue[i];
 				rte_spinlock_unlock(&vq->access_lock);
 			}
 		}