Update on "[Executorch][BE] Rename sdpa_with_kv_cache.py to custom_ops.py"

Because now we have more than sdpa_with_kv_cache in it

Differential Revision: [D66269486](https://our.internmc.facebook.com/intern/diff/D66269486/)

[ghstack-poisoned]

Author: kimishpatel

examples/models/llama/source_transformation/quantized_kv_cache.py

@@ -190,7 +190,6 @@ def update(self, input_pos, k_val, v_val):
                 seq_length = k_val.size(dim_to_slice)
                 narrowed_k = k_out.narrow(dim_to_slice, start_pos, seq_length)
                 narrowed_k.copy_(k_val)
-                # pyre-ignore: Incompatible parameter type [6]
                 narrowed_v = v_out.narrow(dim_to_slice, start_pos, seq_length)
                 narrowed_v.copy_(v_val)
             else: