drm/msm/a6xx: update/fix CP_PROTECT initialization

Update CP_PROTECT register programming based on downstream.

A6XX_PROTECT_RW is renamed to A6XX_PROTECT_NORDWR to make things aligned
and also be more clear about what it does.

Note that this required switching to use the CP_ALWAYS_ON_COUNTER as the
GMU counter is not accessible from the cmdstream.  Which also means
using the CPU counter for the msm_gpu_submit_flush() tracepoint (as
catapult depends on being able to compare this to the start/end values
captured in cmdstream).  This may need to be revisited when IFPC is
enabled.

Also, compared to downstream, this opens up CP_PERFCTR_CP_SEL as the
userspace performance tooling (fdperf and pps-producer) expect to be
able to configure the CP counters.

Fixes: 4b565ca5

 ("drm/msm: Add A6XX device support")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Akhil P Oommen <akhilpo@codeaurora.org>
Link: https://lore.kernel.org/r/20210513171431.18632-5-jonathan@marek.ca
[switch to CP_ALWAYS_ON_COUNTER, open up CP_PERFCNTR_CP_SEL, and spiff
 up commit msg]
Signed-off-by: Rob Clark <robdclark@chromium.org>