Structured kernel definition for upsample_nearest2d (#50189)
Summary:
See the structured kernel definition [RFC](https://github.com/pytorch/rfcs/pull/9) for context.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50189
Reviewed By: mrshenli
Differential Revision: D25903846
Pulled By: soulitzer
fbshipit-source-id: 0059fda9b7d86f596ca35d830562dd4b859293a0
