Mark mv as CompositeExplicitAutograd (#67373)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/67373
From the implementation of mv, it's decomposed into addmv. So it should
be a CompositeExplicitAutograd op.
Test Plan: It shouldn't change any behaviors. So, CI.
Reviewed By: bdhirsh
Differential Revision: D31973265
Pulled By: alanwaketan
fbshipit-source-id: 3b6850f08e6f671b908a177f148cc6194baa8a13
