This patch makes use of the newly introduced sbcap library, and
introduces new code (and extends existing one) to handle all the aspects
of MME peers talking SBc-AP and its underlaying SCTP connection.
This commit doesn't aim to implement all the SBc-AP features, but to
implement a minimal subset of features already available for CBSP in
osmo-cbc, in order to have similar support level for both 2G and 4G
networks.
Related: OS#4945
Change-Id: Ib278bc1d1a74459814016fef7a8fe21cc29d46c9
Pau Espin