netdev-dpdk: Fix vhost namespace with 21.11-rc2.

vhost ops is now prefixed with rte_ [1].

1: https://git.dpdk.org/dpdk/commit/?id=e7c727c307d7

Signed-off-by: David Marchand <david.marchand@redhat.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>

lib/netdev-dpdk.c

@@ -181,7 +181,7 @@ static int vring_state_changed(int vid, uint16_t queue_id, int enable);
 static void destroy_connection(int vid);
 static void vhost_guest_notified(int vid);
 
-static const struct vhost_device_ops virtio_net_device_ops =
+static const struct rte_vhost_device_ops virtio_net_device_ops =
 {
     .new_device =  new_device,
     .destroy_device = destroy_device,