[llvm] [mlir] [mlir python] Add nanobind support for standalone dialects. (PR #117922)

[Peter Hawkins via llvm-commits]

hawkinsp wrote:

> Thanks @hawkinsp - looking forward to more `nb::...` 😄

I'm actually a pretty good fraction of the way through porting the MLIR Python core to nanobind as well, and I've made enough progress that I can get the JAX CPU test suite to pass. It has mostly been mechanical, with a few small changes to deal with various semantic differences. I'll open another PR for that when it's closer to ready, and I guess there's some sort of RFC process we'll need to follow as well.

https://github.com/llvm/llvm-project/pull/117922