drm/amdgpu: initialze ras caps per paltform config

Driver only manages GFX/SDMA/MMHUB RAS in platforms
that gpu node is connected to cpu through XGMI, other
than that, it queries VBIOS for RAS capabilities.

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: John Clements <John.Clements@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>