[llvm] [clang-tools-extra] [clang] [CLANG] Add warning when INF or NAN are used in a binary operation or as function argument in fast math mode. (PR #76873)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman approved this pull request.

The changes LGTM aside from some minor improvements to the tests.

https://github.com/llvm/llvm-project/pull/76873