[Doc] Update Qwen documentation (#9869)

Author: jeejeelee

docs/source/models/supported_models.rst

@@ -277,7 +277,7 @@ Text Generation
   * - :code:`QWenLMHeadModel`
     - Qwen
     - :code:`Qwen/Qwen-7B`, :code:`Qwen/Qwen-7B-Chat`, etc.
-    -
+    - ✅︎
     - ✅︎
   * - :code:`Qwen2ForCausalLM`
     - Qwen2
@@ -516,7 +516,7 @@ Text Generation
     - Qwen-VL
     - T + I\ :sup:`E+`
     - :code:`Qwen/Qwen-VL`, :code:`Qwen/Qwen-VL-Chat`, etc.
-    -
+    - ✅︎
     - ✅︎
   * - :code:`Qwen2AudioForConditionalGeneration`
     - Qwen2-Audio
@@ -540,6 +540,9 @@ Text Generation
 | :sup:`E` Pre-computed embeddings can be inputted for this modality.
 | :sup:`+` Multiple items can be inputted per text prompt for this modality.
 
+.. note::
+  vLLM currently only supports adding LoRA to the language backbone of multimodal models.               
+
 .. note::
   For :code:`openbmb/MiniCPM-V-2`, the official repo doesn't work yet, so we need to use a fork (:code:`HwwwH/MiniCPM-V-2`) for now.
   For more details, please see: https://github.com/vllm-project/vllm/pull/4087#issuecomment-2250397630

vllm/model_executor/models/qwen.py

@@ -1048,7 +1048,7 @@ def get_mm_mapping(self) -> MultiModelKeys:
 @MULTIMODAL_REGISTRY.register_max_image_tokens(MAX_QWEN_IMG_TOKENS)
 @INPUT_REGISTRY.register_dummy_data(dummy_data_for_qwen)
 @INPUT_REGISTRY.register_input_processor(input_processor_for_qwen)
-class QWenLMHeadModel(QWenBaseModel):
+class QWenLMHeadModel(QWenBaseModel, SupportsLoRA):
     """
     QWenLMHeadModel is not only applicable to LLM  but also to VL, which is not 
     conducive to the current integration logic of LoRA in vLLM. Therefore, it