onnxruntime

[VitisAI] 1. api compatbile 2. dynamic load onnx (#18470)

### Description
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1. Add a backward-compatible API for compiling model.
2. Run-time load vitisai-ep.dll


### Motivation and Context
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- If it fixes an open issue, please link to the issue here. -->

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Co-authored-by: Yueqing Zhang <yueqingz@amd.com>
Co-authored-by: Zhenze Wang <zhenzew@xilinx.com>