Adds per-op microbenchmarks for NNC (#50845)
Summary:
Runs through vast majority of primitive ops that exist in NNC and benchmarks them against PyTorch ops on CPU. Dumps out a plot like this.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50845
Reviewed By: ngimel
Differential Revision: D25989080
Pulled By: Chillee
fbshipit-source-id: 6d6a39eb06b3de9a999993224d5e718537c0c8c4
