Enable DUS-based KV Cache update for OSS

PiperOrigin-RevId: 705933157

ai_edge_torch/generative/layers/kv_cache.py

@@ -20,6 +20,7 @@
 
 from ai_edge_torch import hlfb
 from ai_edge_torch.generative.layers import model_config
+from ai_edge_torch.generative.utilities.dynamic_update_slice import dynamic_update_slice
 import torch
 import torch.utils._pytree as pytree
 
@@ -159,8 +160,6 @@ def update(
   Returns:
       KVCacheEntry: The updated KVCache entry based on the passed inputs.
   """
-  # Turn dynamic_update_slice updates off for now.
-  use_dus=False
   update_kv_cache = _update_kv_impl if use_dus else _update_kv_base_impl
   return update_kv_cache(cache, input_pos, k_slice, v_slice)