drm/amdgpu: Set clock ungate state when suspend/fini

After set power ungate state, set clock ungate state
before when suspend or fini.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>