[libc] [llvm] [libc][math] Refactor sincosf implementation to header only (PR #177523)

[via llvm-commits]

tnuha wrote:

I've been formatting with `buildifier -r bazel/llvm-project-overlay/libc`, and this consistently doesn't change anything. Is there a preferable way to format?

https://github.com/llvm/llvm-project/pull/177523