[NNC] add support for masked_fill (#48974)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/48974
Test Plan: Imported from OSS
Reviewed By: bertmaher
Differential Revision: D25413165
Pulled By: eellison
fbshipit-source-id: 8cece1dc3692389be90c0d77bd71b103254d5ad3
