net: skb->dst accessors

Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/atm/br2684.c b/net/atm/br2684.c
index bfa8fa9..2912665f 100644
--- a/net/atm/br2684.c
+++ b/net/atm/br2684.c
@@ -228,7 +228,7 @@
 	struct br2684_dev *brdev = BRPRIV(dev);
 	struct br2684_vcc *brvcc;
 
-	pr_debug("br2684_start_xmit, skb->dst=%p\n", skb->dst);
+	pr_debug("br2684_start_xmit, skb_dst(skb)=%p\n", skb_dst(skb));
 	read_lock(&devs_lock);
 	brvcc = pick_outgoing_vcc(skb, brdev);
 	if (brvcc == NULL) {