[Feature] Support for Ascend NPU backend (#3853)

Signed-off-by: Song Zhang <gepin.zs@antgroup.com>
Co-authored-by: 22dimensions <waitingwind@foxmail.com>

python/sglang/srt/configs/device_config.py

@@ -10,7 +10,7 @@ class DeviceConfig:
     device: Optional[torch.device]
 
     def __init__(self, device: str = "cuda") -> None:
-        if device in ["cuda", "xpu", "hpu", "cpu"]:
+        if device in ["cuda", "xpu", "hpu", "cpu", "npu"]:
             self.device_type = device
         else:
             raise RuntimeError(f"Not supported device type: {device}")