drm/nouveau/gsp: add display class ids to gpu hal

Use display class IDs from nvkm_rm_gpu, instead of copying them from the
non-GSP HALs.

Removes the AD102 display HAL, which is no longer required as there's no
support for it without GSP-RM.

Signed-off-by: Ben Skeggs <bskeggs@nvidia.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Timur Tabi <ttabi@nvidia.com>
Tested-by: Timur Tabi <ttabi@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>