Enable complex autograd for `index`, add `index` and `index_put` OpInfos (#54562)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/53605
Pull Request resolved: https://github.com/pytorch/pytorch/pull/54562
Reviewed By: malfet
Differential Revision: D27300086
Pulled By: anjali411
fbshipit-source-id: 23e8335e6e4c8f10888b5c54a040880c5b499215
