ipv4: Remember the net in ip_output and ip_mc_output

This is a prepatory patch to passing net int the netfilter hooks,
where net will be used again.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/ip_output.c

@@ -288,11 +288,12 @@ int ip_mc_output(struct sock *sk, struct sk_buff *skb)
 {
 	struct rtable *rt = skb_rtable(skb);
 	struct net_device *dev = rt->dst.dev;
+	struct net *net = dev_net(dev);
 
 	/*
 	 *	If the indicated interface is up and running, send the packet.
 	 */
-	IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
+	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
 
 	skb->dev = dev;
 	skb->protocol = htons(ETH_P_IP);
@@ -347,8 +348,9 @@ int ip_mc_output(struct sock *sk, struct sk_buff *skb)
 int ip_output(struct sock *sk, struct sk_buff *skb)
 {
 	struct net_device *dev = skb_dst(skb)->dev;
+	struct net *net = dev_net(dev);
 
-	IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
+	IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
 
 	skb->dev = dev;
 	skb->protocol = htons(ETH_P_IP);