perf/arm-cmn: Enable per-DTC counter allocation

Finally enable independent per-DTC-domain counter allocation, except on
CMN-600 where we still need to cope with not knowing the domain topology
and thus keep counter indices sychronised across domains. This allows
users to simultaneously count up to 8 targeted events per domain, rather
than 8 globally, for up to 4x wider coverage on maximum configurations.

Even though this now looks deceptively simple, I stand by my previous
assertion that it was a flippin' nightmare to implement; all the real
head-scratchers are hidden in the foundations in the previous patch...

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/849f65566582cb102c6d0843d0f26e231180f8ac.1697824215.git.robin.murphy@arm.com


Signed-off-by: Will Deacon <will@kernel.org>