[llvm] [GISel] Set more MIFlags when translating GEPs (PR #151708)

[Fabian Ritter via llvm-commits]

ritter-x2a wrote:

### Merge activity

* **Aug 4, 11:24 AM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/151708).


https://github.com/llvm/llvm-project/pull/151708