Integrate LLVM at llvm/llvm-project@4d700ffe67be
Integrate LLVM at llvm/llvm-project@4d700ffe67be

Updates LLVM usage to match
[4d700ffe67be](https://github.com/llvm/llvm-project/commit/4d700ffe67be)

PiperOrigin-RevId: 473009759

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