support qwen2 running on ascend npu device (#7022)

Co-authored-by: 刁莹煜 <diaoyingyu1@hisilicon.com>

python/sglang/srt/layers/quantization/utils.py

@@ -6,11 +6,12 @@ from typing import List, Mapping, Tuple, Union
 import torch
 
 from sglang.srt.layers.quantization.fp8_kernel import scaled_fp8_quant
-from sglang.srt.utils import is_cuda
+from sglang.srt.utils import is_cuda, is_npu
 
 _is_cuda = is_cuda()
+_is_npu = is_npu()
 
-if not _is_cuda:
+if not _is_cuda and not _is_npu:
     from vllm._custom_ops import scaled_fp8_quant