Add fix for double allocation MiGraphX EP (#27551)
### Description
Fixing double allocation problem for migraphx-ep.
### Motivation and Context
As an alternative to PR:
https://github.com/microsoft/onnxruntime/pull/25801
Authored-by: Tianlei Wu <tianleiwu>
Co-authored-by: Tianlei Wu <tlwu@microsoft.com>
