[clang] [clang-tools-extra] [compiler-rt] [flang] [lld] [lldb] [llvm] [mlir] [openmp] [pstl] Finally formalise our defacto line-ending policy (PR #86318)

[Chris B via cfe-commits]

https://github.com/llvm-beanz approved this pull request.

I'm happy with this approach. We can adjust and iteratively address issues if any appear.

https://github.com/llvm/llvm-project/pull/86318