[SK_BUFF]: Introduce skb_mac_header()

For the places where we need a pointer to the mac header, it is still legal to
touch skb->mac.raw directly if just adding to, subtracting from or setting it
to another layer header.

This one also converts some more cases to skb_reset_mac_header() that my
regex missed as it had no spaces before nor after '=', ugh.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wan/syncppp.c b/drivers/net/wan/syncppp.c
index 218f7b5..67fc67c 100644
--- a/drivers/net/wan/syncppp.c
+++ b/drivers/net/wan/syncppp.c
@@ -227,7 +227,7 @@
 	unsigned long flags;
 
 	skb->dev=dev;
-	skb->mac.raw=skb->data;
+	skb_reset_mac_header(skb);
 
 	if (dev->flags & IFF_RUNNING)
 	{