Update base for Update on "[ET-VK] Quantized Int8 Convolution"

See the below diff; this diff implements int8 quantized conv2d using the quantized linear layer introduced below.

Note that the current implementation doesn't yet support depthwise convs; a specialized implementation will need to be added for that.

Differential Revision: [D81330809](https://our.internmc.facebook.com/intern/diff/D81330809/)

[ghstack-poisoned]

Author: ssjia