Move NamedTensorMetaInterface definitions to TensorImpl.h (#26030)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/26030
Test Plan:
- [namedtensor ci]
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26030
Differential Revision: D17322383
Pulled By: zou3519
fbshipit-source-id: d5b914d646b48a6f4e0104aceb435e694b72bd96
