Integrate LLVM at llvm/llvm-project@6d702a1e6a06
Integrate LLVM at llvm/llvm-project@6d702a1e6a06

Updates LLVM usage to match
[6d702a1e6a06](https://github.com/llvm/llvm-project/commit/6d702a1e6a06)

PiperOrigin-RevId: 418784553

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