[Hardware][Intel] OpenVINO vLLM backend (#5379)

vllm/engine/async_llm_engine.py

@@ -393,6 +393,12 @@ class AsyncLLMEngine:
                 "Distributed execution is not supported with the CPU backend.")
             from vllm.executor.cpu_executor import CPUExecutorAsync
             executor_class = CPUExecutorAsync
+        elif engine_config.device_config.device_type == "openvino":
+            assert distributed_executor_backend is None, (
+                "Distributed execution is not supported with "
+                "the OpenVINO backend.")
+            from vllm.executor.openvino_executor import OpenVINOExecutorAsync
+            executor_class = OpenVINOExecutorAsync
         elif engine_config.device_config.device_type == "xpu":
             if distributed_executor_backend is None:
                 from vllm.executor.xpu_executor import XPUExecutorAsync