Quantized Conv2d operator (#20064)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20064
Initial implementation of quantized convolution operator using fbgemm.
Reviewed By: zafartahirov
Differential Revision: D15178352
fbshipit-source-id: 2e5453283137dc165e9a20164ffc138fa8caf88a
