Remove doubly nested anonymous namespace (#68555)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68555
The outer namespace is already anonymous, so this is not necessary.
Test Plan: Imported from OSS
Reviewed By: dagitses
Differential Revision: D32565941
Pulled By: malfet
fbshipit-source-id: 4daf1c46b25ff68e748e6c834c63d759ec6fde4f
