drm/amdgpu/powerplay: implement thermal control for tonga.

Implement thermal and fan control for tonga.

Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
5 files changed