Improve torch.linalg.qr (#50046)
Summary:
This is a follow up of PR https://github.com/pytorch/pytorch/issues/47764 to fix the remaining details.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50046
Reviewed By: zou3519
Differential Revision: D25825557
Pulled By: mruberry
fbshipit-source-id: b8e335e02265e73484a99b0189e4cc042828e0a9
