message: Integrate LLVM at llvm/llvm-project@1a4990a4f71a
  Updates LLVM usage to match
  [1a4990a4f71a](https://github.com/llvm/llvm-project/commit/1a4990a4f71a)
diff: @@ -4,8 +4,8 @@ load("//third_party:repo.bzl", "tf_http_archive")
  def repo(name):
  """Imports LLVM."""
  - LLVM_COMMIT = "99a6d003edbe97fcb94854547276ffad3382ec1d"
  - LLVM_SHA256 = "763f933a1db16a857b8fd5a4a70bb8e9a4ffb83be5e9c2cd86a62b4ed2cb652a"
  + LLVM_COMMIT = "1a4990a4f71adf1ea0b8f7e0ae2ddd8a85f9c393"
  + LLVM_SHA256 = "d5588c2abcad3b36906e050b90f995e8e4b70fecdbd35d81a1174a7feca88a2a"
  tf_http_archive(
  name = name,
  