[Hardware] Support platforms and plugin system (#774)

Signed-off-by: gcanlin <canlinguosdu@gmail.com>

tests/e2e/offline_inference/test_zimage_tensor_parallel.py

@@ -23,7 +23,7 @@ from tests.utils import GPUMemoryMonitor
 from vllm_omni import Omni
 from vllm_omni.diffusion.data import DiffusionParallelConfig
 from vllm_omni.outputs import OmniRequestOutput
-from vllm_omni.utils.platform_utils import is_npu, is_rocm
+from vllm_omni.platforms import current_omni_platform
 
 # os.environ["VLLM_TEST_CLEAN_GPU_MEMORY"] = "1"
 os.environ["VLLM_WORKER_MULTIPROC_METHOD"] = "spawn"
@@ -129,7 +129,7 @@ def _run_zimage_generate(
 
 @pytest.mark.integration
 def test_zimage_tensor_parallel_tp2(tmp_path: Path):
-    if is_npu() or is_rocm():
+    if current_omni_platform.is_npu() or current_omni_platform.is_rocm():
         pytest.skip("Z-Image TP e2e test is only supported on CUDA for now.")
     if not torch.cuda.is_available() or torch.cuda.device_count() < 2:
         pytest.skip("Z-Image TP=2 requires >= 2 CUDA devices.")