OpenBSC - Feature #1630: Implement SI2quater generation in OpenBSC / OsmoBTS
implement SI2quater support
This feature requires changes to both BSc and BTS. This ticket describe BTS side of things, see related #1630 for support in BSC.
Relevant spec: 10.5.2.33b of TS 44.018 version 13.0.0 Release 13
First we need to verify that SI2ter is properly scheduled (osmocom-bb, xgoldmon etc).
Than implement receiving SI2quater from BSC (including fragmentation) and use same verification setup to make sure it's scheduled properly.