[SK_BUFF]: Introduce skb_set_transport_header

For the cases where the transport header is being set to a offset from
skb->data.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 9576745..82543ee 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -261,7 +261,8 @@
 
 	iph->protocol = nexthdr[1];
 	pskb_trim(skb, skb->len - alen - padlen - 2);
-	skb->h.raw = __skb_pull(skb, sizeof(*esph) + esp->conf.ivlen) - ihl;
+	__skb_pull(skb, sizeof(*esph) + esp->conf.ivlen);
+	skb_set_transport_header(skb, -ihl);
 
 	return 0;