[llvm] Reland [llvm] Add support for llvm IR atomicrmw fminimum/fmaximum instructions (PR #137701)

[Jonathan Thackray via llvm-commits]

jthackray wrote:

@kazutakahirata Ok, I've found the issue. I'll submit a PR with you as a reviewer in the next 5 mins.

https://github.com/llvm/llvm-project/pull/137701