Revert "Symintify decomps for split and upsample_bilinear; Fix decomp for _softmax_backward_data and native_dropout_backward (#88761)"
This reverts commit 9eabcc370f4c3a04be85cb1f878038f10716bdc3.
Reverted https://github.com/pytorch/pytorch/pull/88761 on behalf of https://github.com/suo due to much broken https://hud.pytorch.org/pytorch/pytorch/commit/9eabcc370f4c3a04be85cb1f878038f10716bdc3