lib/RAN: Introduce CTRL_CLIENT port to access CTRL muxed in RAN IPA conn

This is the case for SCCPlite between BSC and MSC (or BSC-NAT). MGCP and
CTRL can be multiplexed over the same underlaying IPA conn.

Related: OS#2012
Change-Id: Id90c1609f0439b00379166fb9e4028d181fc023e
2 files changed