If use GART for FB translation, place both vram and gart to sysvm
aperture. AGP aperture is not set up in this case because it
is not used
Signed-off-by: NOak Zeng <Oak.Zeng@amd.com>
Reviewed-by: NChristian Konig <christian.koenig@amd.com>
Reviewed-by: NFelix Kuehling <felix.kuehling@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>