[barefoot]: Add carrier change (oper state) for bf_tun tap intf (#2218)

Author: mkbalani

platform/barefoot/bfn-modules/modules/bf_tun.c

@@ -1073,6 +1073,7 @@ static const struct net_device_ops tap_netdev_ops = {
 	.ndo_features_check	= passthru_features_check,
 	.ndo_set_rx_headroom	= tun_set_headroom,
 	.ndo_get_stats64	= tun_net_get_stats64,
+	.ndo_change_carrier	= tun_change_carrier,
 };
 
 static void tun_flow_init(struct tun_struct *tun)