* bts: Verify PCU socket can disconnect + re-connect
* bts: Add test ensuring only one connection to PCU interface accepted
* Fix use of osmocom-extended RSL Channel Numbers
* L1CTL: Add support for CCCH_MODE_COMBINED_CBCH
* add three tests for CIPHER MODE COMPLETE without algo
* msc: Add a test for LU with invalid MCC/MNC in BSSAP/RANAP
* msc: Separate as_GSUP_SAI from f_mm_auth