inet: toss struct net initialization around

Some places, that deal with ICMP statistics already have where
to get a struct net from, but use it directly, without declaring
a separate variable on the stack.

Since I will need this net soon, I declare a struct net on the
stack and use it in the existing places in a separate patch not
to spoil the future ones.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 7187121..9342cfd 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -354,8 +354,9 @@
 	struct sock *sk;
 	int harderr;
 	int err;
+	struct net *net = dev_net(skb->dev);
 
-	sk = __udp4_lib_lookup(dev_net(skb->dev), iph->daddr, uh->dest,
+	sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
 			iph->saddr, uh->source, skb->dev->ifindex, udptable);
 	if (sk == NULL) {
 		ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);