Support for non-zero zero_points for weight and activation (#23541)
Summary:
We can now have any valid zero points for weight and activation for conv2d kernel.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23541
Test Plan:
buck test mode/dev caffe2/test:quantized -- 'test_qconv\ \(test_quantized.TestQuantizedConv\)' --print-passing-details
```
Running 1 tests
Started new test run: https://our.intern.facebook.com/intern/testinfra/testrun/3377699723897843
✓ caffe2/test:quantized - test_qconv (test_quantized.TestQuantizedConv) 68.528 1/1 (passed)
Test output:
> test_qconv (test_quantized.TestQuantizedConv) ... ok
>
> ----------------------------------------------------------------------
> Ran 1 test in 68.529s
>
> OK
Finished test run: https://our.intern.facebook.com/intern/testinfra/testrun/3377699723897843
Summary (total time 74.97s):
PASS: 1
FAIL: 0
SKIP: 0
FATAL: 0
TIMEOUT: 0
OMIT: 0
```
Differential Revision: D16556515
Pulled By: dskhudia
fbshipit-source-id: 6e2ee9ddc58f9dc8a3f8b25918bb7955f0655073
