llvm-project

9a9e3e3b - [clang-tidy][NFC] Update header guards to match LLVM style (#166669)

[clang-tidy][NFC] Update header guards to match LLVM style (#166669) All detected by https://clang.llvm.org/extra/clang-tidy/checks/llvm/header-guard.html. Some headers didn't have guards, so they were added.