[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index 66f3205..02081bc 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -137,7 +137,7 @@
 	switch (skb->protocol) {
 	case __constant_htons(ETH_P_IP):
 	{
-		struct iphdr *iph = skb->nh.iph;
+		const struct iphdr *iph = ip_hdr(skb);
 		h = iph->daddr;
 		h2 = iph->saddr^iph->protocol;
 		if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&