[clang] [BoundsSafety] Allow 'counted_by' attribute on pointers in structs in C (PR #90786)

[Bill Wendling via cfe-commits]

bwendling wrote:

Ah! I see what you mean. I'll bring this up with the developer. (Actually, that construct makes me nervous about their code in general...)

https://github.com/llvm/llvm-project/pull/90786