[FSDP] Warning when fail to clone (#74946)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/74946
Warn instead of hard failure when fail to clone state_dict, as this
param might not be managed by FSDP and thus we do not expect to clone it.
ghstack-source-id: 152978204
Test Plan: CI
Reviewed By: mrshenli
Differential Revision: D35242306
fbshipit-source-id: d9eb58a2993341040e4a9f36fa388f423bd2ddc5
(cherry picked from commit 6b0d0806349a423be19d31f17b5cb66fd4bf9a82)
