[Runtime] Allow parameter sharing between modules

[yongsun]

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

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[icemelon]

I realize that there's two issues in this PR.

1. The input ndarray is a view created from the ndarray in the storage pool. If you use SetInputZeroCopy to set the input ndarray, it only modifies the data ptr in the input ndarray, but not the data ptr in the storage entry. Therefore, if other intermediate tensor shares the same ndarray in the storage pool, it will still have the data ptr as nullpr.
2. Even if you fix issue 1, there's a follow-up question. If the intermediate tensor requires larger space than the input tensor, it means that using SetInputZeroCopy may not provide enough space for this storage entry.

[yongsun]

Thanks so much for catching the issues! I'll close this PR and find a clean solution.