ipv6: addrconf.c: remove unnecessary "if"

the value of err is always negative if it goes to errout, so we don't need to
check the value of err.
Signed-off-by: Cong Ding <dinggnu@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/addrconf.c

@@ -534,7 +534,6 @@ void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
 	return;
 errout:
-	if (err < 0)
 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
 }