[SK_BUFF]: Use skb_reset_network_header in skb_push cases

skb_push updates and returns skb->data, so we can just call
skb_reset_network_header after the call to skb_push.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index ced2c4b..f84ca66 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -828,7 +828,8 @@
 	}
 
 	skb->h.raw = skb->nh.raw;
-	skb->nh.raw = skb_push(skb, gre_hlen);
+	skb_push(skb, gre_hlen);
+	skb_reset_network_header(skb);
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
 			      IPSKB_REROUTED);