BUG Fixes regression for nllloss gradcheck (#64203)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/64163
This PR includes the fix and the opinfo from https://github.com/pytorch/pytorch/pull/63854/ for non-regression testing.
cc albanD mruberry jbschlosser
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64203
Reviewed By: albanD
Differential Revision: D30647522
Pulled By: jbschlosser
fbshipit-source-id: 2974d299763505908fa93532aca2bd5d5b71f2e9
