drm/amdgpu: Centralize ras cap query to amdgpu_ras_check_supported

Move ras capablity check to amdgpu_ras_check_supported.
Driver will query ras capablity through psp interace, or
vbios interface, or specific ip callbacks.

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>