[llvm-branch-commits] [clang] [clang][driver][clang-cl] Fix unused argument warning for `/std:c++20` for precompiled module inputs to `clang-cl` (PR #102438)

[Chuanqi Xu via llvm-branch-commits]

https://github.com/ChuanqiXu9 milestoned https://github.com/llvm/llvm-project/pull/102438