[llvm] [DA] Rewrite BanerjeeMIV test with safe APInt interval arithmetic (PR #207662)

[Ryotaro Kasuga via llvm-commits]

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kasuga-fj wrote:

- `I` is not defined
- I think the sentence `The total is bounded by ...` is not clear. What does "total" refer to?
- IIRC, the index type can differ from the type of the backedge-taken count. Maybe you need to consider the type of it as well.

https://github.com/llvm/llvm-project/pull/207662