Update on "[ET-VK] Using shared variable to store calculated output pose to free up registers and improve performance."

This diff introduces a shared variable to store calculated output pose in conv2d_pw op to free up registers and improve performance. The code changes include adding a shared variable to hold calculated positions and modifying the existing code to use the shared variable.

Differential Revision: [D67742567](https://our.internmc.facebook.com/intern/diff/D67742567/)

[ghstack-poisoned]

Author: trivedivivek