Don't enforce docstrings on bool dispatch (#15306)
Summary:
Allows 2 functions that are boolean dispatched to have no docstrings (the only case that will fail now is if both functions have docstrings)
Fixes #15281
Pull Request resolved: https://github.com/pytorch/pytorch/pull/15306
Differential Revision: D13494884
Pulled By: driazati
fbshipit-source-id: 65fec39ae03a7d6a68ad617c9b270faeb1617930
