Port xnnpack operators to new registration API (#36800)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36800
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D21089650
Pulled By: ezyang
fbshipit-source-id: 1babdb5524038e3951d3c4303e4ba87e68b4f138
