ip6gre: Allow live link address change

The ip6 GRE tap device should not be forced to down state to change
the mac address and should allow live address change for tap device
similar to ipv4 gre.
Signed-off-by: NShweta Choudaha <schoudah@brocade.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/ip6_gre.c

@@ -1256,6 +1256,8 @@ static int ip6gre_tap_init(struct net_device *dev)
 	if (ret)
 		return ret;
 
+	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+
 	tunnel = netdev_priv(dev);
 
 	ip6gre_tnl_link_config(tunnel, 1);
@@ -1289,6 +1291,7 @@ static void ip6gre_tap_setup(struct net_device *dev)
 
 	dev->features |= NETIF_F_NETNS_LOCAL;
 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 }
 
 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],