Move THPVariable_NewWithVar around (#64550)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64550
Just moves a function around to make the next PR easier to read.
Test Plan: Imported from OSS
Reviewed By: ngimel
Differential Revision: D30867570
Pulled By: albanD
fbshipit-source-id: 99ae925568ed29ca7fdea059762c21d430d4a204
