onnxruntime

[AIX]eigen update fix and test failures fix (#23751)

### Description
Changes in this PR are for:

- Cleanup the patch for Eigen on AIX. Not needed anymore .
- Fix to recent test failures

```
1: [----------] Global test environment tear-down
1: [==========] 4737 tests from 310 test suites ran. (94682 ms total)
1: [  PASSED  ] 4733 tests.
1: [  SKIPPED ] 2 tests, listed below:
1: [  SKIPPED ] MatMulFpQ4.MatMul2DSym
1: [  SKIPPED ] MatMulFpQ4.MatMul2DBlkZp
1: [  FAILED  ] 2 tests, listed below:
1: [  FAILED  ] GraphTransformationTests.MatMulAddFusion_three_input_with_1d
1: [  FAILED  ] GraphTransformationTests.MatMulAddFusion_NeedReshape_3D
```

---------

Co-authored-by: Tianlei Wu <tlwu@microsoft.com>