Fix sinc docs typo (#49667)
Summary:
Fix small typo in sinc docs
Pull Request resolved: https://github.com/pytorch/pytorch/pull/49667
Reviewed By: ngimel
Differential Revision: D25665721
Pulled By: soulitzer
fbshipit-source-id: 5f78b9e34bb0084e51ae79d1afc450bcb0ae3d75
