Cleanup on the Compositions for Devices from mars.

This cleanup also solves ambigious GroundDistanceSrv for MarsAltimeter

In the new orogen_loader setup the GroundDistanceSrv for the MarsAltimeter
could not resolved correctly. It was ambigious between because the wrong
Provider was added to the Composition.
Merge pull request #2 from goldhoorn/altimeter

Resolved ambigious GroundDistanceSrv for MarsAltimeter