net: sched: propagate extack to cls->destroy callbacks

Propagate extack to cls->destroy callbacks when called from
non-error paths.  On error paths pass NULL to avoid overwriting
the failure message.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.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 64c24b4..cd5fe38 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -600,7 +600,7 @@ static int flow_init(struct tcf_proto *tp)
 	return 0;
 }
 
-static void flow_destroy(struct tcf_proto *tp)
+static void flow_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
 {
 	struct flow_head *head = rtnl_dereference(tp->root);
 	struct flow_filter *f, *next;