fix scale and zero_point names (#23991)
Summary:
scale and zero_point name should match with what's used in other methods of the class.
Closes https://github.com/pytorch/pytorch/issues/23881
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23991
Test Plan: buck build mode/opt caffe2/benchmarks/operator_benchmark/pt:qconv_test --show-output
Reviewed By: jianyuh
Differential Revision: D16703956
Pulled By: dskhudia
fbshipit-source-id: 5e894bd84caaa20dc7639d4885d59a72f27d8ec2
