net: sched: sch: add extack for init callback

This patch adds extack support for init callback to prepare per-qdisc
specific changes for extack.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c
index 531250f..49dda30 100644
--- a/net/sched/sch_choke.c
+++ b/net/sched/sch_choke.c
@@ -431,7 +431,8 @@ static int choke_change(struct Qdisc *sch, struct nlattr *opt)
 	return 0;
 }
 
-static int choke_init(struct Qdisc *sch, struct nlattr *opt)
+static int choke_init(struct Qdisc *sch, struct nlattr *opt,
+		      struct netlink_ext_ack *extack)
 {
 	return choke_change(sch, opt);
 }