Fix deepcopy for tensor with MTIA device key. (#107427)
Summary: Tensor with MTIA device type doesn't have storage and we need to treat it same as other tensors which don't have storage.
Test Plan: CI tests.
Differential Revision: D48456004
Pull Request resolved: https://github.com/pytorch/pytorch/pull/107427
Approved by: https://github.com/cx-yin, https://github.com/ezyang
