refactor(stream_generator): update code for transformers>=4.41.1

In line with
https://github.com/huggingface/transformers/blob/eed9ed679878ada2f6d2eefccdbda368cabc88b1/src/transformers/generation/utils.py

Author: eginhard

TTS/tts/layers/xtts/stream_generator.py

@@ -201,16 +201,15 @@ def generate(  # noqa: PLR0911
 
         # 5. Prepare `input_ids` which will be used for auto-regressive generation
         if self.config.is_encoder_decoder:
-            input_ids = self._prepare_decoder_input_ids_for_generation(
-                batch_size,
-                decoder_start_token_id=generation_config.decoder_start_token_id,
-                bos_token_id=generation_config.bos_token_id,
+            input_ids, model_kwargs = self._prepare_decoder_input_ids_for_generation(
+                batch_size=batch_size,
+                model_input_name=model_input_name,
                 model_kwargs=model_kwargs,
+                decoder_start_token_id=generation_config.decoder_start_token_id,
                 device=inputs_tensor.device,
             )
         else:
-            # if decoder-only then inputs_tensor has to be `input_ids`
-            input_ids = inputs_tensor
+            input_ids = inputs_tensor if model_input_name == "input_ids" else model_kwargs.pop("input_ids")
 
         # 6. Prepare `max_length` depending on other stopping criteria.
         input_ids_seq_length = input_ids.shape[-1]