ip6tnl,gre6,vti6: implement ndo_get_iflink

Don't use dev->iflink anymore.

CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 53d90ed..b531484 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -601,8 +601,6 @@
 		dev->flags |= IFF_POINTOPOINT;
 	else
 		dev->flags &= ~IFF_POINTOPOINT;
-
-	dev->iflink = p->link;
 }
 
 /**
@@ -808,6 +806,7 @@
 	.ndo_do_ioctl	= vti6_ioctl,
 	.ndo_change_mtu = vti6_change_mtu,
 	.ndo_get_stats64 = ip_tunnel_get_stats64,
+	.ndo_get_iflink = ip6_tnl_get_iflink,
 };
 
 /**