drm/msm: Add per-context perfcntr state

drm/msm: Add per-context perfcntr state

The upcoming PERFCNTR_CONFIG ioctl will allow for both global counter
collection, and per-context counter reservation for local (ie. within
a single GEM_SUBMIT ioctl) counter collection.

Any number of contexts can reserve the same counters, but we will need
to ensure that counters reserved for local counter collection do not
conflict with counters used for global counter collection.

So add tracking for per-context local counter reservations.

Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Anna Maniscalco <anna.maniscalco2000@gmail.com>
Reviewed-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/728211/
Message-ID: <20260526145137.160554-10-robin.clark@oss.qualcomm.com>