[clang] Fix array bound checker false negative (PR #161723)

[Rashmi Mudduluru via cfe-commits]

t-rasmud wrote:

Summary: The bounds checker needs an aggressive mode.  This needs to be paired with ways of expressing invariants that allow the programmer to show that a value is in bounds.  This could be understanding span, understanding bounds annotations from Firebloom/Evo, or C++ contracts.  We don’t plan to do any work on this soon. Closing the PR.

https://github.com/llvm/llvm-project/pull/161723