[clang] [clang-cl] Accept `cl`-style output arguments (`/Fo`, `-Fo`) for `--fmodule-output` (PR #121046)

[Chuanqi Xu via cfe-commits]

ChuanqiXu9 wrote:

> Ready for review; all relevant tests passing.

I think @rnk was saying you should add a test for this.

https://github.com/llvm/llvm-project/pull/121046