sch: make htb_rate_cfg and functions around that generic

As it is going to be used in tbf as well, push these to generic code.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 2d06c2a..2761c90 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -679,4 +679,23 @@
 }
 #endif
 
+struct psched_ratecfg {
+	u64 rate_bps;
+	u32 mult;
+	u32 shift;
+};
+
+static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
+				unsigned int len)
+{
+	return ((u64)len * r->mult) >> r->shift;
+}
+
+extern void psched_ratecfg_precompute(struct psched_ratecfg *r, u32 rate);
+
+static inline u32 psched_ratecfg_getrate(const struct psched_ratecfg *r)
+{
+	return r->rate_bps >> 3;
+}
+
 #endif