[BUG] Optimize reshape will add new split OP

[yaoxingwei]

Hi, When I use onnxsim to optimize the GPT-NEO model. The reshape subgraph is:

After optimize, the reshape will not be optimized, and a new split OP will be added:

It seems the reshape structure is the standard structure will be optimized. If any suggestion for the issue? Thanks.

Model GPT-NEO ONNX model

Thanks.