[nnc] Lazy lowerings registration; custom classes network params (#67623)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/67623
Test Plan: Imported from OSS
Reviewed By: ZolotukhinM
Differential Revision: D32065076
Pulled By: IvanKobzarev
fbshipit-source-id: 4945ac6483938d428c539ed1ce4fcd6988b34250
