[SK_BUFF]: Introduce arp_hdr(), remove skb->nh.arph

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index c4cec17..496b062 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -363,7 +363,7 @@
 
 	skb_reset_network_header(skb);
 	skb->h.raw = skb->data;
-	arp = skb->nh.arph;
+	arp = arp_hdr(skb);
 
 	if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
 	     arp->ar_hrd != htons(ARPHRD_IEEE802)) ||