[llvm] [Analysis] Guard logf128 cst folding (PR #106543)

[Thomas Preud'homme via llvm-commits]

RoboTux wrote:

My usecase is a bit atypical in that I run CMake on one machine and build on another so it's useful for me to be able to disable features that rely on headers not available widely (in this case via LLVM_HAS_LOGF128 set to OFF). I do this because the system where I build doesn't have CMake support but as I said, I realize it's atypical though. I've left a comment about using llvm/Config/config.h.cmake which is easier for us to override and would make it more consistent with other checks of system features.

https://github.com/llvm/llvm-project/pull/106543