Mark package as arch independent

[sertonix]

Otherwise the generated file will check whenever the 32/64 bit-ness matches. Since this is a header only library this check shouldn't exist.

Ref https://cmake.org/cmake/help/latest/module/CMakePackageConfigHelpers.html#generating-a-package-version-file

[arximboldi]

Thank you very much!

It seems there are some formatting issues in the CMake code, can you please run cmake-format, ideally in the nix-shell so it uses the same version as we do... also running the nix-shell will set up some pre-commit hooks that will prevent this issue in the future.

[sertonix]

cmake-format now passes but it is basically just working around the fact that cmake-format doesn't understand ARCH_INDEPENDENT: cmakelang/parse/funs/standard_modules.py#L1891

[arximboldi]

Thank you! Agree that it looked better before but tooling is key :)