net: sched: constify tcf_proto and tc_action

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index 34533a5..6994214 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -356,7 +356,7 @@
 	}
 }
 
-static int flow_classify(struct sk_buff *skb, struct tcf_proto *tp,
+static int flow_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 			 struct tcf_result *res)
 {
 	struct flow_head *head = tp->root;