[clang] [clang-format] Fix a bug in annotating function declaration names (PR #76206)

[Owen Pan via cfe-commits]

owenca wrote:

See [here](https://discourse.llvm.org/t/why-are-the-breaks-sometimes-removed-when-alwaysbreakafterreturntype-is-all/75780/4?u=owenpan) for background info.

https://github.com/llvm/llvm-project/pull/76206