[bug] `AffineApplyNormalizer` assert Error

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When running my code using cgeist with the --raise-scf-to-affine option, I encountered the following error:
> cgeist: ../lib/polygeist/Passes/AffineCFG.cpp:534: AffineApplyNormalizer::AffineApplyNormalizer(mlir::AffineMap, llvm::ArrayRef, mlir::PatternRewriter&, mlir::DominanceInfo&): Assertion `isValidSymbolInt(t, false)' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.

Use the following minimal code example (saved as test.c) that reproduces the error，run the code using `cgeist test.c --raise-scf-to-affine --function=* -S --memref-fullrank -o test.mlir`
```c
void nested_loop_using_variable_as_step(int vali[20][30]) {
int stepx = vali[0][0];
for (int x = 0; x < 20; x++) {
for (int y = 1; y < 30; y += stepx) {
vali[x][y] = 1;
}
}
}
```

Start with lib/polygeist/Passes/AffineCFG.cpp at AffineApplyNormalizer::AffineApplyNormalizer, then reproduce the assertion using the supplied test.c and cgeist command with --raise-scf-to-affine. Trace the failing symbol validation for the variable loop step; done means this reproducer no longer triggers the assertion and produces the expected output.

Written by the indexing model from the issue text.