Integrate LLVM at llvm/llvm-project@6706a4720ffc
Integrate LLVM at llvm/llvm-project@6706a4720ffc

Updates LLVM usage to match
[6706a4720ffc](https://github.com/llvm/llvm-project/commit/6706a4720ffc)

PiperOrigin-RevId: 408566046

tensorflow/runtime,tensorflow/runtime,tensorflow/runtime,tensorflow/runtime