drm/amd/powerplay: support sw smu hotspot and memory temperature retrieval

Support hotspot and memory temperature retrieval on sw smu routine.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>