net: Remove __skb_insert() calls outside of skbuff internals.

This minor cleanup simplifies later changes which will convert
struct sk_buff and friends over to using struct list_head.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/cassini.c b/drivers/net/cassini.c
index f1936d5..40ff6a9 100644
--- a/drivers/net/cassini.c
+++ b/drivers/net/cassini.c
@@ -2182,7 +2182,7 @@
 	 * do any additional locking here. stick the buffer
 	 * at the end.
 	 */
-	__skb_insert(skb, flow->prev, (struct sk_buff *) flow, flow);
+	__skb_queue_tail(flow, skb);
 	if (words[0] & RX_COMP1_RELEASE_FLOW) {
 		while ((skb = __skb_dequeue(flow))) {
 			cas_skb_release(skb);
diff --git a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c
index ddccc07..98e0495 100644
--- a/drivers/net/ppp_generic.c
+++ b/drivers/net/ppp_generic.c
@@ -1864,7 +1864,7 @@
 	for (p = list->next; p != (struct sk_buff *)list; p = p->next)
 		if (seq_before(seq, p->sequence))
 			break;
-	__skb_insert(skb, p->prev, p, list);
+	__skb_queue_before(list, p, skb);
 }
 
 /*
diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c
index ff175e8..185b1df 100644
--- a/drivers/net/pppol2tp.c
+++ b/drivers/net/pppol2tp.c
@@ -353,7 +353,7 @@
 	spin_lock_bh(&session->reorder_q.lock);
 	skb_queue_walk_safe(&session->reorder_q, skbp, tmp) {
 		if (PPPOL2TP_SKB_CB(skbp)->ns > ns) {
-			__skb_insert(skb, skbp->prev, skbp, &session->reorder_q);
+			__skb_queue_before(&session->reorder_q, skbp, skb);
 			PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG,
 			       "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n",
 			       session->name, ns, PPPOL2TP_SKB_CB(skbp)->ns,