Move OMP/MKL thread initialization into ATen/Parallel (#19011)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19011
ghimport-source-id: 432e31eccfd0e59fa21a790f861e6b2ff4fdbac6
Differential Revision: D14846034
Pulled By: ilia-cher
fbshipit-source-id: d9d03c761d34bac80e09ce776e41c20fd3b04389
