mesh: Switch beaconing net key

When transitioning from Phase 1 to Phase 2 of a network key and we are
beaconing, we need to halt the beaconing on the old key version, and
begin beaconing on the new key version.

mesh/net.c

@@ -2625,13 +2625,29 @@ static int key_refresh_phase_two(struct mesh_net *net, uint16_t idx)
 	if (subnet->kr_phase == KEY_REFRESH_PHASE_TWO)
 		return MESH_STATUS_SUCCESS;
 
+	/* Stop beaconing on old key */
+	if (net->snb_enable)
+		net_key_beacon_disable(subnet->net_key_tx, false);
+
+	if (net->mpb_enable)
+		net_key_beacon_disable(subnet->net_key_tx, true);
+
 	subnet->key_refresh = 1;
 	subnet->net_key_tx = subnet->net_key_upd;
 	/*
 	 * TODO: Provisioner may need to stay in phase three until
 	 * it hears beacons from all the nodes
 	 */
 	subnet->kr_phase = KEY_REFRESH_PHASE_TWO;
+
+	/* Start beaconing on new key */
+	if (net->snb_enable)
+		net_key_beacon_enable(subnet->net_key_tx, false, 0);
+
+	if (net->mpb_enable)
+		net_key_beacon_enable(subnet->net_key_tx, true,
+							net->mpb_period);
+
 	refresh_beacon(subnet, net);
 	queue_friend_update(net);