sit/gre6: don't try to add the same route two times

addrconf_add_linklocal() already adds the link local route, so there is no
reason to add it before calling this function.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -2682,7 +2682,6 @@ static void addrconf_sit_config(struct net_device *dev)
 		struct in6_addr addr;
 
 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
-		addrconf_prefix_route(&addr, 64, dev, 0, 0);
 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
 			addrconf_add_linklocal(idev, &addr);
 		return;
@@ -2709,8 +2708,6 @@ static void addrconf_gre_config(struct net_device *dev)
 	}
 
 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
-	addrconf_prefix_route(&addr, 64, dev, 0, 0);
-
 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
 		addrconf_add_linklocal(idev, &addr);
 }