Fixes exponential with lambda=0 (#36837)
Summary:
Resolves https://github.com/pytorch/pytorch/issues/36798.
In the future more thorough testing would be nice.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36837
Differential Revision: D21102342
Pulled By: mruberry
fbshipit-source-id: 4fae45677e54b403296033720dfb13abca47f3a4
