drm/amdgpu/SRIOV: Navi12 SRIOV VF gets GTT base

With changes in PSP and HV, SRIOV VF will handle

vram gtt location just like bare metal. There is

no need to differentiate it anymore.

Signed-off-by: Jiange Zhao <Jiange.Zhao@amd.com>
Reviewed-by: Emily Deng <Emily.Deng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>