drm/powerplay: Add smu set xgmi pstate interface

XGMI pstate is controlled by SMU, driver need this interface to communicate
with SMU

Signed-off-by: shaoyunl <shaoyun.liu@amd.com>
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2 files changed