[clang] [Clang][counted_by] Don't treat a __bdos argument as an array if it isn't (PR #125298)

[Bill Wendling via cfe-commits]

bwendling wrote:

I got a testcase from creduce. It's similar to your testcase. Basically, it's indexing into a pointer field, which isn't going to give the correct result either way. I expect that it's indexing into an array instead.

https://github.com/llvm/llvm-project/pull/125298