[llvm] [SelectionDAG] Lower llvm.ldexp.f32 to ldexp() on Windows. (PR #95301)

[Matt Arsenault via llvm-commits]

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

I find the weird base class handling of same-os-different-target strangle to begin with 

https://github.com/llvm/llvm-project/pull/95301