BatchNorm: Remove dispatch in parallel region (#60596)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/60596
Ref #56794
Test Plan: Imported from OSS
Reviewed By: jbschlosser
Differential Revision: D29446193
Pulled By: ngimel
fbshipit-source-id: 3ebf44a5f1e001e7dc42cd5963752b7e5b9bcbd9
