[Bug] [Relay] Error when compiling ONNX with LeakyRelu

[luyaor]

[Bug] [Relay] Error when compiling a simple ONNX model

Description

When compiling following model with TVM, it will error.

The model(with ONNX as frontend) with error is as follows, check bug.onnx in bug5.zip.

I think it is because ONNX allows attribute alpha in LeakyRelu with a default value 0.01. Please check LpPool in ONNX: https://github.com/onnx/onnx/blob/master/docs/Operators.md#leakyrelu

Error Log

Traceback (most recent call last):
  File "check.py", line 11, in <module>
    mod, params = relay.frontend.from_onnx(onnx_model, {})
  File "/Users/luyaor/Documents/tvm/python/tvm/relay/frontend/onnx.py", line 2806, in from_onnx
    mod, params = g.from_onnx(graph, opset, freeze_params)
  File "/Users/luyaor/Documents/tvm/python/tvm/relay/frontend/onnx.py", line 2613, in from_onnx
    op = self._convert_operator(op_name, inputs, attr, opset)
  File "/Users/luyaor/Documents/tvm/python/tvm/relay/frontend/onnx.py", line 2721, in _convert_operator
    sym = convert_map[op_name](inputs, attrs, self._params)
  File "/Users/luyaor/Documents/tvm/python/tvm/relay/frontend/common.py", line 603, in __call__
    return get_relay_op(self._new_name)(*inputs, **attrs)
TypeError: leaky_relu() missing 1 required positional argument: 'alpha'

How to reproduce

Environment

Python3, with tvm, onnx

tvm version: c31e338 Wed Dec 9 14:52:58 2020 +0900

1. Download bug5.zip
2. Run python check.py.

[luyaor]

Fixed in #7259.