Clarify, make consistent, and test the behavior of logspace when dtype is integral (#47647)
Summary:
torch.logspace doesn't seem to have explained how integers are handled.
Add some clarification and some test when dtype is integral.
The CUDA implementation is also updated to be consistent with CPU implementation.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/47647
Reviewed By: gchanan
Differential Revision: D25843351
Pulled By: walterddr
fbshipit-source-id: 45237574d04c56992c18766667ff1ed71be77ac3
