[llvm] [NVPTX] Add NewPM codegen pipeline (PR #215712)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

> IIRC, we were switching between old/new PM via clang flags, so I guess it was affecting both opt and llc related parts of the pipeline. It's been a while back, so I do not recall the details.

This was likely the middle-end transition (which shouldn't have impacted the `llc` pipeline). CodeGen NewPM hasn't really happened yet. I've turned it on for Lanai/MSP430, but I'm not sure many users (especially those using ToT) care about those targets.

https://github.com/llvm/llvm-project/pull/215712