drm/amdgpu: Protect GPU register accesses in powergated state in some paths

drm/amdgpu: Protect GPU register accesses in powergated state in some paths

[ Upstream commit 39fc2bc4da0082c226cbee331f0a5d44db3997da ]

Ungate GPU CG/PG in device_fini_hw and device_halt to protect GPU
register accesses, e.g. GC registers are accessed in amdgpu_irq_disable_all()
and amdgpu_fence_driver_hw_fini().

Signed-off-by: Yifan Zhang <yifan1.zhang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>