[SK_BUFF]: unions of just one member don't get anything done, kill them

Renaming skb->h to skb->transport_header, skb->nh to skb->network_header and
skb->mac to skb->mac_header, to match the names of the associated helpers
(skb[_[re]set]_{transport,network,mac}_header).

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ip6_tunnel.c

@@ -701,7 +701,7 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
 			goto discard;
 		}
 		secpath_reset(skb);
-		skb->mac.raw = skb->nh.raw;
+		skb->mac_header = skb->network_header;
 		skb_reset_network_header(skb);
 		skb->protocol = htons(protocol);
 		skb->pkt_type = PACKET_HOST;
@@ -898,7 +898,7 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
 	dst_release(skb->dst);
 	skb->dst = dst_clone(dst);
 
-	skb->h.raw = skb->nh.raw;
+	skb->transport_header = skb->network_header;
 
 	proto = fl->proto;
 	if (encap_limit >= 0) {