[clang-tools-extra] [clang-tidy]avoid bugprone-unused-return-value false positive for function with the same prefix as the default argument (PR #84333)

[Oliver Stöneberg via cfe-commits]

firewave wrote:

I think this might also require documentation changes.

The documentation is also a bit misleading in terms of the defaults: https://clang.llvm.org/extra/clang-tidy/checks/bugprone/unused-return-value.html. I add issues detecting a custom function as it required the ``::` prefix.

https://github.com/llvm/llvm-project/pull/84333