update ONNX supported models info

test_model_zoo.md

@@ -39,7 +39,7 @@
 | Vgg11_bn | [torchvison.model.vgg11_bn](https://github.com/pytorch/vision/blob/master/torchvision/models/vgg.py) |9|
 | Vgg19| [torchvison.model.vgg16_bn](https://github.com/pytorch/vision/blob/master/torchvision/models/vgg.py) |9|
 | Densenet121 | [torchvison.model.densenet121](https://github.com/pytorch/vision/blob/master/torchvision/models/densenet.py) |9|
-| Alexnet | [onnx official](https://github.com/pytorch/vision/blob/master/torchvision/models/alexnet.py) |9|
+| Alexnet | [torchvison.model.alexnet](https://github.com/pytorch/vision/blob/master/torchvision/models/alexnet.py) |9|
 | Shufflenet | [onnx official](https://github.com/onnx/models/tree/master/vision/classification/shufflenet) |9|
 | Inception_v2 | [onnx official](https://github.com/onnx/models/tree/master/vision/classification/inception_and_googlenet/inception_v2) |9|