drm/amdgpu: add vram_type and vram_bit_width for interface query (v2)

Track the type of vram on the board and provide a query for it.
User mode drivers and tools want this information for determining
bandwidth information and form informational purposes.

v2: fix build when CI support is not enabled

Signed-off-by: Ken Wang <Qingqing.Wang@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>