[lld] [llvm] Rename `F_no_mmap` to `F_mmap` (PR #134787)

[Dmitry Chestnykh via llvm-commits]

chestnykh wrote:

> Thanks! Can you add a link of the patch that introduced F_no_mmap to the description?

Ofc, done

https://github.com/llvm/llvm-project/pull/134787