[llvm] [NVPTX] Add patterns for fma.relu.{f16|f16x2|bf16|bf16x2} (PR #114977)

[Hugh Delaney via llvm-commits]

hdelan wrote:

I've also added extra cases so that `nnan .. fma` in the same pattern will allow the emission of `fma.relu`

https://github.com/llvm/llvm-project/pull/114977