* isort all files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* [NPU] apply npu_identity to conv bn and copy2cpu, test=develop

* update npu identity to share data with x, test=develop

* address review comments, test=develop

* [NPU] add _npu_identity op and api, test=develop

* fix doc

* address comments