[nnc] Enable fusion of bfloat16 ops (#64196)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/64196
Test Plan: Imported from OSS
Reviewed By: ZolotukhinM
Differential Revision: D30643864
Pulled By: bertmaher
fbshipit-source-id: e95edeaf7089464d713ea1d1f951743d3e5f61c5
