drm/amdgpu/atomfirmware: implement vram_width for APUs

Implement support using the new atomfirmware system info table.

Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2 files changed