tvmc: solve a linting error on onnx command line driver frontend (apa…

…che#6536)

* Updates onnx load function from "load" (a compatibility attribute)
   to "load_model" (the actual function)

 * Add a pylint command, that we don't see currently on upstream CI,
   but it reproduces when linting it locally.

python/tvm/driver/tvmc/frontends.py

@@ -154,6 +154,7 @@ def load(self, path):
         # pylint: disable=C0415
         import onnx
 
+        # pylint: disable=E1101
         model = onnx.load(path)
 
         # pylint: disable=E1101