UPSTREAM: perf/arm-cmn: Optimise DTM counter reads

When multiple nodes of the same type are connected to the same XP
(particularly in CAL configurations), it seems that they are likely
to be consecutive in logical ID. Therefore, we're likely to gain a
small benefit from an easy tweak to optimise out consecutive reads
of the same set of DTM counters for an aggregated event.

Bug: 247832918
Change-Id: Iab3e36dbbbd22426930ff058b4245dab0e266955
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/7777d77c2df17693cd3dabb6e268906e15238d82.1638530442.git.robin.murphy@arm.com


Signed-off-by: Will Deacon <will@kernel.org>
(cherry picked from commit 847eef94)
Signed-off-by: Robin Peng <robinpeng@google.com>