drm/amdgpu: Normalize reg offsets on VCN v4.0.3

Remote access to external AIDs isn't possible with VCN RRMT disabled
and it is disabled on SoCs with GC 9.4.4, so use only local offsets.

Signed-off-by: Sathishkumar S <sathishkumar.sundararaju@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>