BSC_ConnectionHandler: introduce ctrl interface

There are some upcomming tests which require to access the control
interface of the MSC while the actual test is running. Future test
cases (e.g. Paging, see also Change Id:
a6a1a6bd6da1bf46d6d703be495795d3610ca431) will use this.

Change-Id: Ie3caf7a449311e7687670cadfa27818635d25aa4
Related: OS#3615
Related: OS#3187
2 files changed