[clang] [clang][DependencyScanning] Add a Clang Driver Option to Enable Dependency Scanning Logging (PR #211966)

[Cyndy Ishida via cfe-commits]

https://github.com/cyndyishida commented:

I'm not sure where things stand with the clang driver that supports explicitly built c++20 modules, but should this driver option work in this case? If so, can you add a test for it? If not, what's needed to support it? 

https://github.com/llvm/llvm-project/pull/211966