IPVS: Add sysctl_nat_icmp_send()

In preparation for not including sysctl_nat_icmp_send in
struct netns_ipvs when CONFIG_SYCTL is not defined.
Signed-off-by: Simon Horman <horms@verge.net.au>

net/netfilter/ipvs/ip_vs_core.c

@@ -607,9 +607,16 @@ static int sysctl_snat_reroute(struct sk_buff *skb)
 	return ipvs->sysctl_snat_reroute;
 }
 
+static int sysctl_nat_icmp_send(struct net *net)
+{
+	struct netns_ipvs *ipvs = net_ipvs(net);
+	return ipvs->sysctl_nat_icmp_send;
+}
+
 #else
 
 static int sysctl_snat_reroute(struct sk_buff *skb) { return 0; }
+static int sysctl_nat_icmp_send(struct net *net) { return 0; }
 
 #endif
 
@@ -1074,7 +1081,6 @@ ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
 	struct ip_vs_protocol *pp;
 	struct ip_vs_proto_data *pd;
 	struct ip_vs_conn *cp;
-	struct netns_ipvs *ipvs;
 
 	EnterFunction(11);
 
@@ -1149,11 +1155,10 @@ ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
 	 * Check if the packet belongs to an existing entry
 	 */
 	cp = pp->conn_out_get(af, skb, &iph, iph.len, 0);
-	ipvs = net_ipvs(net);
 
 	if (likely(cp))
 		return handle_response(af, skb, pd, cp, iph.len);
-	if (ipvs->sysctl_nat_icmp_send &&
+	if (sysctl_nat_icmp_send(net) &&
 	    (pp->protocol == IPPROTO_TCP ||
 	     pp->protocol == IPPROTO_UDP ||
 	     pp->protocol == IPPROTO_SCTP)) {