HQQ: PEFT support for HQQ (#30632)

Update quantizer_hqq.py

src/transformers/quantizers/quantizer_hqq.py

@@ -197,4 +197,4 @@ class HqqHfQuantizer(HfQuantizer):
 
     @property
     def is_trainable(self) -> bool:
-        return False
+        return True