[lld] [LLD] [COFF] Fix implicit DLL entry point for MinGW (PR #171680)

[Mateusz Mikuła via llvm-commits]

mati865 wrote:

Thank you for the review.

 I have slightly improved the description and expanded the note with mention of Clang and GCC.

https://github.com/llvm/llvm-project/pull/171680