drm/amdgpu: add Clock and Power Gating support for gc 10.3.6

Add below supports:
GFX Coarse Grain Clock Gating(CGCG)
GFX Coarse grain light sleep/deep sleep(CGLS)
GFX Medium Grain Clock Gating(MGCG)
GFX Medium Grain light sleep/deep sleep(MGLS)
GFX Fine Grain Clock Gating(FGCG)
RLC MGLS
CP  MGLS
MMHUB Clock Gating
SDMA Clock Gating
HDP Clock Gating
ATHUB Clock Gating
IH Clock Gating
GFX Power Gating

Signed-off-by: Yifan Zhang <yifan1.zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>