[clang] [Clang][Driver] Revise Cygwin ToolChain to call linker directly (PR #147960)

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jeremyd2019 wrote:

Oh, another proposed implementation to look at: #74933  I was planning to refer to that, MinGW.cpp, and the GCC spec for Cygwin, and see if I could come up with a couple of places where virtual functions could be added to the MinGW::Linker class so that Cygwin::Linker could derive from it and override (I think the "wrap" stuff and list of default libraries)

https://github.com/llvm/llvm-project/pull/147960