[NET]: Remove HIPPI private from skbuff.h

This removes the private element from skbuff, that is only used by
HIPPI. Instead it uses skb->cb[] to hold the additional data that is
needed in the output path from hard_header to device driver.

PS: The only qdisc that might potentially corrupt this cb[] is if
netem was used over HIPPI. I will take care of that by fixing netem
to use skb->stamp. I don't expect many users of netem over HIPPI

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/802/hippi.c

@@ -51,6 +51,7 @@ static int hippi_header(struct sk_buff *skb, struct net_device *dev,
 			unsigned len)
 {
 	struct hippi_hdr *hip = (struct hippi_hdr *)skb_push(skb, HIPPI_HLEN);
+	struct hippi_cb *hcb = (struct hippi_cb *) skb->cb;
 
 	if (!len){
 		len = skb->len - HIPPI_HLEN;
@@ -84,9 +85,10 @@ static int hippi_header(struct sk_buff *skb, struct net_device *dev,
 	if (daddr)
 	{
 		memcpy(hip->le.dest_switch_addr, daddr + 3, 3);
-		memcpy(&skb->private.ifield, daddr + 2, 4);
+		memcpy(&hcb->ifield, daddr + 2, 4);
 		return HIPPI_HLEN;
 	}
+	hcb->ifield = 0;
 	return -((int)HIPPI_HLEN);
 }