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/packet/af_packet.c b/net/packet/af_packet.c
index 6da9f38..4f76e55 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -372,8 +372,7 @@
 		goto oom;
 
 	/* drop any routing info */
-	dst_release(skb->dst);
-	skb->dst = NULL;
+	skb_dst_drop(skb);
 
 	/* drop conntrack reference */
 	nf_reset(skb);
@@ -621,8 +620,7 @@
 
 	skb_set_owner_r(skb, sk);
 	skb->dev = NULL;
-	dst_release(skb->dst);
-	skb->dst = NULL;
+	skb_dst_drop(skb);
 
 	/* drop conntrack reference */
 	nf_reset(skb);