Fix ControlNetModel.from_unet do not load add_embedding (#7269)

* Fix ControlNetModel.from_unet do not load add_embedding

* delete white space in blank line

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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>

src/diffusers/models/controlnet.py

@@ -509,6 +509,9 @@ class ControlNetModel(ModelMixin, ConfigMixin, FromOriginalControlNetMixin):
             if controlnet.class_embedding:
                 controlnet.class_embedding.load_state_dict(unet.class_embedding.state_dict())
 
+            if hasattr(controlnet, "add_embedding"):
+                controlnet.add_embedding.load_state_dict(unet.add_embedding.state_dict())
+
             controlnet.down_blocks.load_state_dict(unet.down_blocks.state_dict())
             controlnet.mid_block.load_state_dict(unet.mid_block.state_dict())