[clang] [CIR] Introduce IntTypeInterface to allow uniform integer types handling (PR #146660)

[Henrich Lauko via cfe-commits]

xlauko wrote:

### Merge activity

* **Jul 2, 2:25 PM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/146660).


https://github.com/llvm/llvm-project/pull/146660