Remove backward ops for miopen transposed convolution (#70063)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/70063
Test Plan: Imported from OSS
Reviewed By: albanD
Differential Revision: D33171170
Pulled By: jbschlosser
fbshipit-source-id: 4fd6c1cd027f714354644c4ac7694d0f9092c762
