Enable fast pass tensor_fill for single element complex tensors (#50383)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/50383
Test Plan: Imported from OSS
Reviewed By: heitorschueroff
Differential Revision: D25879881
Pulled By: anjali411
fbshipit-source-id: a254cff48ea9a6a38f7ee206815a04c31a9bcab0