[llvm] [MIPS] Implement llvm.fminimum and llvm.fmaximum with f32/f64 (PR #89907)

[YunQiang Su via llvm-commits]

wzssyqa wrote:

I think that this logic may introduce better performance:

```
if (a>b) {
	return a;
}
if (a<b) {
	return b;
}
if (a == b) {
	if (a == -0)  // with GPR instead of FPR.
		return b;
	return a;
}
if (a unordered 0) {
	return a;
} else {
	return b;
}
```
Can you have consider it?
It's due to that we process the most cases as early as possible.

https://github.com/llvm/llvm-project/pull/89907