Validate NCHWc binary input ranks (#33060)
This pull request improves the robustness of the NCHWc optimizer by
ensuring that binary operations are only transformed when all input
tensors have the expected rank (number of dimensions). It also adds a
new test to verify this behavior.
**NCHWc optimizer robustness:**
* Updated `TransformBinary` in `nchwc_transformer.cc` to check that all
input tensors have the expected number of dimensions (`kNchwcDims`)
before proceeding with transformation, preventing incorrect
transformations on tensors with unexpected rank.
* Fixed usage of shape variables in the dimension comparison logic to
avoid referencing potentially uninitialized pointers.
**Testing improvements:**
* Added a new test case
`BinaryInputsWithUnexpectedRankAreNotTransformed` in
`nchwc_optimizer_test.cc` to ensure that binary operations with inputs
of unexpected rank are not transformed by the optimizer. The test
verifies that the `Add` operation remains in the graph when input ranks
do not match expectations.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
