[clang] [X86_32][C++] fix 0 sized struct case in vaarg. (PR #86388)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

If you implement #86075 like I suggested, the inconsistency here also goes away, I think: if va_arg queries classifyArgumentType, you get the same result as argument lowering, so clang becomes self-consistent.  (Whether that's gcc-compatible is a different question...)

https://github.com/llvm/llvm-project/pull/86388