[PKT_SCHED]: Kill TCF_META_ID_TCCLASSID.

Thomas Graf states:

> I used to mark such ids as obsolete in the header but since
> skb is on diet anyway and there has been no official
> iproute2 release with the ematch bits included it might be
> a better idea to remove the ids from the header completely.
> Those that have picked up my patch on netdev shouldn't care
> about a ABI breakage, actually I doubt that someone is using
> it already.

So here's the patch to remove it.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>