[clang] [clang] Reject VLAs in `__is_layout_compatible()` (PR #87737)

[via cfe-commits]

cor3ntin wrote:

I think the current behavior is reasonable-ish. Rejecting specific types is a bit weird... I think VLA should model incomplete types (but we currently don't reject that either, which is a bug)

IE, I would expect  __is_layout_compatible to return false in the presence of VLAs, incomplete types, and FAM

https://github.com/llvm/llvm-project/pull/87737