Instead of setting the active VRAM size directly provide a the info if
we can use the buffer functions or not.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NChunming zhou <david1.zhou@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>