Remove backward ops for cuDNN transposed convolution (#69902)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/69902
Test Plan: Imported from OSS
Reviewed By: albanD
Differential Revision: D33093795
Pulled By: jbschlosser
fbshipit-source-id: 8b90150bd1996e48c0c888bdab4e95a849d10ef5
