[llvm] [CodingStandard] Rework anonymous namespace section to cover visibility more broadly (PR #126775)

[Rahul Joshi via llvm-commits]

jurahul wrote:

> > Thanks, applied your suggestions.
> 
> Thanks! Do you need us to land this for you?

No. I have commit access, will land once the checks are green again.

https://github.com/llvm/llvm-project/pull/126775