[SofaKernel] Use links for input and output topologies of the barycentric mapping

[jnbrunet]

Something, when having multiple topologies in the same node as the input state, the barycentric mapping will get the wrong input topology since it rely only on fromModel->getContext. This PR fixes this by adding links for the input and output topologies.

Also some reformatting of the input topology type detection with a goto statement...a good example as to where goto can be useful :-)

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This PR:

• builds with SUCCESS for all platforms on the CI.
• does not generate new warnings.
• does not generate new unit test failures.
• does not generate new scene test failures.
• does not break API compatibility.
• is more than 1 week old (or has fast-merge label).

Reviewers will merge only if all these checks are true.

[hugtalbot]

[ci-build][with-all-tests]