convert onnx to stablehlo can not transform onnx.EntryPoint

[endaiHW]

I tried using onnx-mlir to convert ONNX dialect to StableHLO, but noticed that onnx.EntryPoint() wasn't eliminated in the output. It seems that onnx.EntryPoint() primarily serves as a marker for function entry points. Can I directly remove it during the conversion process?

[AlexandreEichenberger]

At IBM, we don't use StableHLO, so I would not know if it's fine or not. I would do a PR and add as reviewers (or ask us to add them) folks that have recently update StableHLO.