Publicly expose `cub::detail::ptx_compute_cap` and deprecate `cub::PtxVersion`

#8728 is adding a new internal primitive `cub::detail::ptx_cc` that returns the compute capability of the PTX of the cubin that will be run on the current device when a kernel is launched. This function offers the same functionality as `cub::PtxVersion`, but is strongly typed. We should expose it at the public API as a replacement of `cub::PtxVersion`.