Merge topic 'cpack-zstd-parallel'

525faec4e9 CPack: Add parallel zstd compression
215c4efd3e cmArchiveWrite: Factor out thread count selection
29f63129be CPack: Format CPACK_THREADS compression methods as a definition list

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !7003