Inline contents of simple cmake/thirdparty files

[harrism]

Prompted by a comment from @vyasr rapidsai/rmm#1558 (comment)

We should eliminate cmake/thirdparty/x.cmake files that have just these two repeated lines in them:

# Use CPM to find or clone CCCL
function(find_and_configure_cccl)

  include(${rapids-cmake-dir}/cpm/cccl.cmake)
  rapids_cpm_cccl(BUILD_EXPORT_SET rmm-exports INSTALL_EXPORT_SET rmm-exports)

endfunction()

find_and_configure_cccl()

As Vyas pointed out, these files are trivial and repetitive, and lead to more code to maintain than just inlining the include and rapids_cpm_x call.

I propose two things:

1. Add a new function to rapids-cmake that allows including a list of its module includes:

rapids_cpm_include(cccl.cmake, fmt.cmake, nvtx.cmake)

This would expand to

include(${rapids-cmake-dir}/cpm/cccl.cmake)
include(${rapids-cmake-dir}/cpm/fmt.cmake)
include(${rapids-cmake-dir}/cpm/nvtx.cmake)

2. In all RAPIDS repos, replace cmake/thirdparty/x.cmake files that only contain include and rapids_cpm_x with a single call to rapids_cpm_include and inlined rapids_cpm_x, like so:

rapids_cpm_include(cccl.cmake, fmt.cmake, nvtx.cmake)
rapids_cpm_cccl(BUILD_EXPORT_SET rmm-exports INSTALL_EXPORT_SET rmm-exports)
rapids_cpm_nvtx3(BUILD_EXPORT_SET rmm-exports INSTALL_EXPORT_SET rmm-exports)
rapids_cpm_fmt(BUILD_EXPORT_SET rmm-exports INSTALL_EXPORT_SET rmm-exports)

Note that more complex cmake/thirdparty/x.cmake files should be kept. For example: https://github.com/rapidsai/rmm/blob/branch-24.06/cmake/thirdparty/get_spdlog.cmake