[PKT_SCHED]: Convert tc action functions to single skb pointers

tcf_action_exec only gets a single skb pointer and doesn't own the skb,
but passes double skb pointers (to a local variable) to the action
functions. Change to use single skb pointers everywhere.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/mirred.c b/net/sched/mirred.c
index 20d0691..4fcccbd 100644
--- a/net/sched/mirred.c
+++ b/net/sched/mirred.c
@@ -158,12 +158,11 @@
 }
 
 static int
-tcf_mirred(struct sk_buff **pskb, struct tc_action *a, struct tcf_result *res)
+tcf_mirred(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
 {
 	struct tcf_mirred *p = PRIV(a, mirred);
 	struct net_device *dev;
 	struct sk_buff *skb2 = NULL;
-	struct sk_buff *skb = *pskb;
 	u32 at = G_TC_AT(skb->tc_verd);
 
 	spin_lock(&p->lock);