[clang] [Clang] Fix missing diagnostic for non-standard layout type in `offsetof` (PR #65246)

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kasuga-fj wrote:

Ah, thanks. Then what should I do? Can I make another commit with the same content as the last commit and force push? (sorry, I don't fully understand the LLVM's PR rules)

https://github.com/llvm/llvm-project/pull/65246