[clang] Reland Print library module manifest path again (PR #84881)

[Chuanqi Xu via cfe-commits]

ChuanqiXu9 wrote:

> The file we're looking for is `modules.json`; Renaming it `libc++.modules.json` like `.so` / `.a` file might be a better idea which could avoid name clashes when installed in `/usr/lib`.

BTW, how do you feel about the paragraph. I thought it as a defect in some level.

https://github.com/llvm/llvm-project/pull/84881