[Cake] Fixing iproute2 compile

["Toke Høiland-Jørgensen" <toke@toke.dk>]

So finally got iproute2 to compile out of the kau.toke.dk repo. The
patch below was needed to cake. Posting it here rather than just
committing in the hope of getting someone (Jonathan?) to take a look at
it and fix it everywhere it's needed :)

-Toke

diff --git a/tc/q_cake.c b/tc/q_cake.c
index 4d64405..1384a46 100644
--- a/tc/q_cake.c
+++ b/tc/q_cake.c
@@ -495,7 +496,7 @@ static int cake_print_xstats(struct qdisc_util *qu, FILE *f,
 
 	} else if (stnc->version >= 1 && stnc->version < 0xFF
 				&& stnc->max_tins == TC_CAKE_MAX_TINS
-				&& RTA_PAYLOAD(xstats) >= offsetof(*stnc, capacity_estimate))
+				&& RTA_PAYLOAD(xstats) >= offsetof(typeof(*stnc), capacity_estimate))
 	{
 		int i;