drm/amdgpu: Enable CG for IH v4.4.2

Enable clock gating on IH v4.4.2 versions.

Signed-off-by: Asad kamal <asad.kamal@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>