message: Integrate LLVM at llvm/llvm-project@78c22fbce991
  Updates LLVM usage to match
  [78c22fbce991](https://github.com/llvm/llvm-project/commit/78c22fbce991)
diff: @@ -685,8 +685,8 @@ def tf_repositories(path_prefix = "", tf_repo_name = ""):
  )
  # Check out LLVM and MLIR from llvm-project.
  - LLVM_COMMIT = "49a6502cd5c2361d9c6f49ae1ee36940afbdeb0a"
  - LLVM_SHA256 = "f835c69bc357770002fc36e2cbb20186dac98ddc9d031aff52ba419cc30a3eeb"
  + LLVM_COMMIT = "78c22fbce991bb5ef49db36473b71fc4386e1e85"
  + LLVM_SHA256 = "c4913a0ba27976ff2e04b616bff243806eda121ba9f856f7f65d764a2eab37ec"
  LLVM_URLS = [
  "https://storage.googleapis.com/mirror.tensorflow.org/github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT),
  "https://github.com/llvm/llvm-project/archive/{commit}.tar.gz".format(commit = LLVM_COMMIT),
  