Add some functions for manipulating mkldnn tensors to TORCH_API (#56954)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/56954
Test Plan: Imported from OSS
Reviewed By: jamesr66a
Differential Revision: D28010327
Pulled By: bertmaher
fbshipit-source-id: 59872a40c7bc06187f0d87046446dd39193a1d71
