Integrate LLVM at llvm/llvm-project@86e604c4d685
Integrate LLVM at llvm/llvm-project@86e604c4d685

Updates LLVM usage to match
[86e604c4d685](https://github.com/llvm/llvm-project/commit/86e604c4d685)

PiperOrigin-RevId: 352105071

google-research/structured-additive-IR,google-research/structured-additive-IR