Make SparseNormalize backwards compatible (#25660)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25660
As title
Test Plan:
buck test caffe2/caffe2/python/operator_test:sparse_normalize_test
https://our.intern.facebook.com/intern/testinfra/testrun/5910974517813190
Reviewed By: boryiingsu
Differential Revision: D17187839
fbshipit-source-id: 1e5a6eaac0e825db4ae969540a1f689444070579
