Create empty host tensor for MTIA device type. (#108198)
Summary: Before copying tensor from CPU memory to device memory, for MTIA device, it doesn't need to pin the host memory first.
Test Plan: See diff D48761820
Reviewed By: jackm321
Differential Revision: D48456471
Pull Request resolved: https://github.com/pytorch/pytorch/pull/108198
Approved by: https://github.com/cx-yin, https://github.com/fduwjj
