[VitisAI] Cache node subgraph when necessary (#22073)
### Description
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[VitisAI] Cache node subgraph when necessary
### 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: Zhenze Wang <zhenzew@xilinx.com>
Co-authored-by: zhenzew <zhenzew@amd.com>
