net: sched: cls: add extack support for delete callback

This patch adds extack support for classifier delete callback api. This
prepares to handle extack support inside each specific classifier
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 933058b..7f772da 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -672,7 +672,8 @@ static void u32_destroy(struct tcf_proto *tp)
 	tp->data = NULL;
 }
 
-static int u32_delete(struct tcf_proto *tp, void *arg, bool *last)
+static int u32_delete(struct tcf_proto *tp, void *arg, bool *last,
+		      struct netlink_ext_ack *extack)
 {
 	struct tc_u_hnode *ht = arg;
 	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);