Update base for Update on "[Executorch][llama] Enable quantized sdpa"

Enable leveraging quantized sdpa op when quantized kv cache is used. Instead of adding yet another arg, at the moment I have chosen to leverage quantize_kv_cache option.

Differential Revision: [D71833064](https://our.internmc.facebook.com/intern/diff/D71833064/)

[ghstack-poisoned]

Author: kimishpatel