Move conv to mkldnn (#51483)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51483
This PR moves the conv weights of a frozen model to MKLDNN, and AOT reorders the weights. When the weights are already in MKLDNN, just computing a single conv by converting the input and output from/to mkldnn provides large speedups. I benchmark'd the results of the top 200 shapes in predictor [here](https://www.internalfb.com/phabricator/paste/view/P171537938), as well as verified that it sped up popular models in torchvision.
Test Plan: Imported from OSS
Reviewed By: navahgar
Differential Revision: D26696703
Pulled By: eellison
fbshipit-source-id: 0b4441bee4f6e0890a4540fbca3bb5e58b8c5adf
