i915/guc: Reset engine utilization buffer before registration

i915/guc: Reset engine utilization buffer before registration

[ Upstream commit abcc2ddae5f82aa6cfca162e3db643dd33f0a2e8 ]

On GT reset, we store total busyness counts for all engines and
re-register the utilization buffer with GuC. At that time we should
reset the buffer, so that we don't get spurious busyness counts on
subsequent queries.

To repro this issue, run igt@perf_pmu@busy-hang followed by
igt@perf_pmu@most-busy-idle-check-all for a couple iterations.

Fixes: 77cdd054dd2c ("drm/i915/pmu: Connect engine busyness stats from GuC to pmu")
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241127174006.190128-2-umesh.nerlige.ramappa@intel.com
(cherry picked from commit abd318237fa6556c1e5225529af145ef15d5ff0d)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>