drm/nouveau/pci: add PRI address of config space mirror to nvkm_pci_func

These registers have moved on GH100/GBxxx, and the GSP-RM init code uses
hardcoded values from earlier GPUs to fill GspSystemInfo.

Replace the per-GPU accessors in nvkm_pci_func with region info, and use
it when initialising GspSystemInfo.

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>