[Training] make DreamBooth SDXL LoRA training script compatible with torch.compile (#6483)

* make it torch.compile comaptible

* make the text encoder compatible too.

* style

examples/dreambooth/train_dreambooth_lora_sdxl.py

@@ -780,13 +780,12 @@ def encode_prompt(text_encoders, tokenizers, prompt, text_input_ids_list=None):
             text_input_ids = text_input_ids_list[i]
 
         prompt_embeds = text_encoder(
-            text_input_ids.to(text_encoder.device),
-            output_hidden_states=True,
+            text_input_ids.to(text_encoder.device), output_hidden_states=True, return_dict=False
         )
 
         # We are only ALWAYS interested in the pooled output of the final text encoder
         pooled_prompt_embeds = prompt_embeds[0]
-        prompt_embeds = prompt_embeds.hidden_states[-2]
+        prompt_embeds = prompt_embeds[-1][-2]
         bs_embed, seq_len, _ = prompt_embeds.shape
         prompt_embeds = prompt_embeds.view(bs_embed, seq_len, -1)
         prompt_embeds_list.append(prompt_embeds)
@@ -1429,7 +1428,8 @@ def main(args):
                         timesteps,
                         prompt_embeds_input,
                         added_cond_kwargs=unet_added_conditions,
-                    ).sample
+                        return_dict=False,
+                    )[0]
                 else:
                     unet_added_conditions = {"time_ids": add_time_ids.repeat(elems_to_repeat_time_ids, 1)}
                     prompt_embeds, pooled_prompt_embeds = encode_prompt(
@@ -1443,8 +1443,12 @@ def main(args):
                     )
                     prompt_embeds_input = prompt_embeds.repeat(elems_to_repeat_text_embeds, 1, 1)
                     model_pred = unet(
-                        noisy_model_input, timesteps, prompt_embeds_input, added_cond_kwargs=unet_added_conditions
-                    ).sample
+                        noisy_model_input,
+                        timesteps,
+                        prompt_embeds_input,
+                        added_cond_kwargs=unet_added_conditions,
+                        return_dict=False,
+                    )[0]
 
                 # Get the target for loss depending on the prediction type
                 if noise_scheduler.config.prediction_type == "epsilon":