net: use reciprocal_scale() helper

Replace open codings of (((u64) <x> * <y>) >> 32) with reciprocal_scale().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 063b726..cc56c8b 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -77,7 +77,8 @@
 	hash = jhash_3words((__force u32)keys.dst,
 			    (__force u32)keys.src ^ keys.ip_proto,
 			    (__force u32)keys.ports, q->perturbation);
-	return ((u64)hash * q->flows_cnt) >> 32;
+
+	return reciprocal_scale(hash, q->flows_cnt);
 }
 
 static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,