drm/amdgpu: new cache coherence change for Aldebaran

To support new cache coherence HW on A+A platform mainly in KFD.

Signed-off-by: Eric Huang <jinhuieric.huang@amd.com>
Reviewed-by: Oak Zeng <Oak.Zeng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>