Integrate LLVM at llvm/llvm-project@bfb4c0c37078
Integrate LLVM at llvm/llvm-project@bfb4c0c37078

Updates LLVM usage to match
[bfb4c0c37078](https://github.com/llvm/llvm-project/commit/bfb4c0c37078)

PiperOrigin-RevId: 428446115

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