net_sched: Add size table for qdiscs

Add size table functions for qdiscs and calculate packet size in
qdisc_enqueue().

Based on patch by Patrick McHardy
 http://marc.info/?l=linux-netdev&m=115201979221729&w=2

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index b358c70..f4d386c 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -482,6 +482,7 @@
 	TCA_RATE,
 	TCA_FCNT,
 	TCA_STATS2,
+	TCA_STAB,
 	__TCA_MAX
 };