tun: allow setting ethernet addresss while running

This is a pure software device, and ok with live address change.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tun.c

@@ -849,6 +849,7 @@ static void tun_net_init(struct net_device *dev)
 		/* Ethernet TAP Device */
 		ether_setup(dev);
 		dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+		dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 
 		eth_hw_addr_random(dev);