ipvs: reset ipvs pointer in netns

	Make sure net->ipvs is reset on netns cleanup or failed
initialization. It is needed for IPVS applications to know that
IPVS core is not loaded in netns.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Hans Schillstrom <hans.schillstrom@ericsson.com>
Signed-off-by: Simon Horman <horms@verge.net.au>

net/netfilter/ipvs/ip_vs_core.c

@@ -1924,6 +1924,7 @@ static int __net_init __ip_vs_init(struct net *net)
 control_fail:
 	ip_vs_estimator_net_cleanup(net);
 estimator_fail:
+	net->ipvs = NULL;
 	return -ENOMEM;
 }
 
@@ -1936,6 +1937,7 @@ static void __net_exit __ip_vs_cleanup(struct net *net)
 	ip_vs_control_net_cleanup(net);
 	ip_vs_estimator_net_cleanup(net);
 	IP_VS_DBG(2, "ipvs netns %d released\n", net_ipvs(net)->gen);
+	net->ipvs = NULL;
 }
 
 static void __net_exit __ip_vs_dev_cleanup(struct net *net)