[clang] [LifetimeSafety] Correctly place lifetimebound attr in corner cases (PR #181699)

[Maksim Ivanov via cfe-commits]

https://github.com/emaxx-google approved this pull request.

Looks good, thanks! (I couldn't come up with better ideas on how to implement these checks.)

https://github.com/llvm/llvm-project/pull/181699