When running LDom binding/unbinding test, kernel may panic
in ldmvsw_open(). It is more likely that because we're removing
the ldc connection before unregistering the netdev in vsw_port_remove(),
we set up a window of time where one process could be removing the
device while another trying to UP the device. This also sometimes causes
vio handshake error due to opening a device without closing it completely.
We should unregister the netdev before we disable the "hardware".
Orabug: 
25980913, 
25925306
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
                del_timer_sync(&port->vio.timer);
 
                napi_disable(&port->napi);
+               unregister_netdev(port->dev);
 
                list_del_rcu(&port->list);
 
 
                dev_set_drvdata(&vdev->dev, NULL);
 
-               unregister_netdev(port->dev);
                free_netdev(port->dev);
        }