[clang] [clang-tools-extra] [llvm] [clang][headers] Need a way for math.h to share the definitions of INIFINITY and NAN with float.h (PR #164348)

[Michael Spencer via cfe-commits]

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

lgtm from a modules perspective, but it would be good to have an additional approver.

https://github.com/llvm/llvm-project/pull/164348