[clang] [clang][NFC] Annotate `Type` bit-fields with `clang::preferred_type` (PR #70349)

[Vlad Serebrennikov via cfe-commits]

Endilll wrote:

Formatting is good. I created a PR against `clang-format` to convince the tool: https://github.com/llvm/llvm-project/pull/70360

https://github.com/llvm/llvm-project/pull/70349