Fix saliency maps order for h-cls in cpp

[sovrasov]

What does this PR do?

The order could have been twisted, because logits in hierarchical classification are not placed in the same order as "labels" in model info.

Fixes # (issue)

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests?

[sovrasov]

cpp part is fine, so we can merge this