As GraphRuntime does not provide control-flow logics, we have to split
our model to two parts. While we need to share parameters between them
to save memory usage.

Solution:
1) add "lazy_init_input" in graph's attributes
   "attrs": {
     ... ...
     "lazy_init_input": [
       "list_str",
       [
         "p0"
       ]
     ]
    }
2) allow un-allocated NDArray entry in SetupStorage
3) utilize "set_input_zero_copy" function to set parameters