[Cake] [PATCH] Split tin stats to its own structure to decrease size of tc_cake_xstats

[Dave Taht]

The puzzling thing about the reported error for this function is that
the static analysis checker is complaining about 1400+ bytes being
used *on the stack* (in gnet_stats_copy-app?) for the pa-risc
architecture, and that arch, only, which I just don't "get".

That said, this patch will end up copying less data most of the time,
and fool the static analysis checker in that case.