sage.geometry.polyhedron: Split out backend_cdd_rdf from backend_cdd

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(cherry-picked from #32432)


CC:  @kliem

Component: **geometry**

Author: **Matthias Koeppe**

Branch/Commit: **[`57919d4`](https://github.com/sagemath/sagetrac-mirror/commit/57919d4091e9be8ebc566b2ee7aff8972a325ef6)**

Reviewer: **Jonathan Kliem**

_Issue created by migration from https://trac.sagemath.org/ticket/32592_

