[llvm] Add llvm-binary-utilities to .github/CODEOWNERS (PR #65545)

[Fangrui Song via llvm-commits]

MaskRay wrote:

Merging this as we have some changes that do not have reviewers set (e.g. some llvm-nm patches). I think this should be fixed soon.

https://github.com/llvm/llvm-project/pull/65545