[clang] [flang] [flang] Link to libatomic with openmp and rtlib=libgcc (PR #112202)

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https://github.com/NimishMishra approved this pull request.

LGTM! Thanks for this.

The Windows CI failure seems to be in `Driver/atomic.f90`. Do we disable this test on Windows (if there is a way to do so)?

https://github.com/llvm/llvm-project/pull/112202