Make gen_op_registration flake8 compliant (#47604)
Summary:
Fixes regression introduced by D24686838 (https://github.com/pytorch/pytorch/commit/8182558c22544bfe8ecf37b574460b8448e065b4)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/47604
Reviewed By: walterddr
Differential Revision: D24832687
Pulled By: malfet
fbshipit-source-id: e9f7a35561c2b1705e11fd11abe402e3c83cf5cc
