[FX] fix split_util by using getattr_recursive instead of getattr (#80011)
Summary: If the model contains ModuleList, it's possible that we got some of the weight attributes as module.sub.0.weight. `getattr` doesn't work in this case and we have a dedicated function `getattrt_recursive` for that. Just use that.
Reviewed By: houseroad
Differential Revision: D37326955
Pull Request resolved: https://github.com/pytorch/pytorch/pull/80011
Approved by: https://github.com/houseroad
