Integrate LLVM at llvm/llvm-project@8f0c673d20e7
Integrate LLVM at llvm/llvm-project@8f0c673d20e7

Updates LLVM usage to match
[8f0c673d20e7](https://github.com/llvm/llvm-project/commit/8f0c673d20e7)

PiperOrigin-RevId: 401410827

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