[Patch]: Nokia: make hopping a user changeable parameter

Dear Holger, Thanks for the commit on my previous patch. Here is a new one: This pacth makes hopping type (baseband or RF) a user changeable parameter. Tested with: - MetroSite: baseband and RF hopping works - UltraSite: RF hopping works As previously, the default behavior of OpenBSC is not changed. If the configuration parameter is not provided, it will default to baseband hopping, as before. It builds against the latest version of OpenBSC master. Regards, Csaba