net-sched: change tcf_destroy_chain() to clear start of filter list

Pass double tcf_proto pointers to tcf_destroy_chain() to make it
clear the start of the filter list for more consistency.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index 3352734..8e5f70b 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -160,7 +160,7 @@
 	*prev = flow->next;
 	pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 	qdisc_destroy(flow->q);
-	tcf_destroy_chain(flow->filter_list);
+	tcf_destroy_chain(&flow->filter_list);
 	if (flow->sock) {
 		pr_debug("atm_tc_put: f_count %d\n",
 			file_count(flow->sock->file));
@@ -588,8 +588,7 @@
 	pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 	/* races ? */
 	while ((flow = p->flows)) {
-		tcf_destroy_chain(flow->filter_list);
-		flow->filter_list = NULL;
+		tcf_destroy_chain(&flow->filter_list);
 		if (flow->ref > 1)
 			printk(KERN_ERR "atm_destroy: %p->ref = %d\n", flow,
 			       flow->ref);