[NET]: Split skb->csum

... into anonymous union of __wsum and __u32 (csum and csum_offset resp.)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index e9d4671..4913f25 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -504,7 +504,7 @@
 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
 		th->check = ~tcp_v4_check(th, len,
 					  inet->saddr, inet->daddr, 0);
-		skb->csum = offsetof(struct tcphdr, check);
+		skb->csum_offset = offsetof(struct tcphdr, check);
 	} else {
 		th->check = tcp_v4_check(th, len, inet->saddr, inet->daddr,
 					 csum_partial((char *)th,
@@ -526,7 +526,7 @@
 
 	th->check = 0;
 	th->check = ~tcp_v4_check(th, skb->len, iph->saddr, iph->daddr, 0);
-	skb->csum = offsetof(struct tcphdr, check);
+	skb->csum_offset = offsetof(struct tcphdr, check);
 	skb->ip_summed = CHECKSUM_PARTIAL;
 	return 0;
 }