Update on "[ET-VK] Using shared memory to save position in conv2d dw output op."

This diff introduces a change to conv2d dw op to save output positions in shared memory, which reduces register usage and improves performance.

Differential Revision: [D68400890](https://our.internmc.facebook.com/intern/diff/D68400890/)

[ghstack-poisoned]

Author: trivedivivek