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

[Cinhi Young via llvm-commits]

Cyanoxygen wrote:

```
./build/bin/llvm-lit --path ~/.local/lib/llvm llvm/test/CodeGen/Mips/mipsr6-minmaxnum.ll
-- Testing: 1 tests, 1 workers --
PASS: LLVM :: CodeGen/Mips/mipsr6-minmaxnum.ll (1 of 1)

Testing Time: 0.07s

Total Discovered Tests: 1
  Passed: 1 (100.00%)
```

Maybe the problem is on this merge `b8ae81f`. Rebasing the branch.

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