[llvm] [LoongArch] Fix fptoui.sat miscompilation with NaN inputs (PR #179366)

[Zhaoxin Yang via llvm-commits]

ylzsx wrote:

@nikic Thanks, you’ve identified the root cause. But can we use `ISD::FMAXIMUMNUM/ISD::FMINIMUMNUM` to replace `ISD::FMAXNUM/ISD::FMINNUM`? 

https://github.com/llvm/llvm-project/pull/179366