[Reland] Avoid saving self for `softmax` and `log_softmax` (#66018)
Summary:
Reland of https://github.com/pytorch/pytorch/pull/65242
The last attempt of the reland automatically rebased onto stable, which did not yet have the revert commit
Pull Request resolved: https://github.com/pytorch/pytorch/pull/66018
Reviewed By: albanD
Differential Revision: D31348822
Pulled By: soulitzer
fbshipit-source-id: 881d701b404530c1352ac9245bd67264e1652b8a
