[llvm] AMDGPU/NewPM: Fill out passes in addCodeGenPrepare (PR #102867)

[Matt Arsenault via llvm-commits]

arsenm wrote:

### Merge activity

* **Aug 20, 3:25 PM EDT**: @arsenm started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/102867).


https://github.com/llvm/llvm-project/pull/102867