[clang] [AST][NFC] Rename and refactor floating-point status checks in AST and ByteCode evaluators (PR #213750)

[Hubert Tong via cfe-commits]

https://github.com/hubert-reinterpretcast approved this pull request.

LGTM; thanks! Please wait for a day or two to see if other reviewers have additional concerns.

https://github.com/llvm/llvm-project/pull/213750