[caffe2] simplify caffe2 code with fbgemm handling block size 1 emb (#33774)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33774
Simplify caffe2 code using D19246900
Test Plan: CI
Reviewed By: jianyuh
Differential Revision: D20102410
fbshipit-source-id: 8de4d9cfac66898db0718ac6477339fd5e5428e3
