drm/amdgpu: add PTL enable/query gfx control support for GC 9.4.4
Introduce hardware detection, runtime state tracking and a
kgd->ptl_ctrl() callback to enable/disable/query PTL via the
PSP performance-monitor interface (commands 0xA0000000/1).
The driver now exposes PTL capability to KFD and keeps the
software state in sync with the hardware.
Signed-off-by: Perry Yuan <perry.yuan@amd.com> Reviewed-by: Lijo Lazar <lijo.lazar@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>