sysmobts: avoid sending duplicate RSL CHAN ACT ACK
sysmobts: avoid sending duplicate RSL CHAN ACT ACK

This is just an intermediary hack, until we get proper lchan manager
threads...

geosphere/osmo-bts,shimaore/osmo-bts,osmocom/osmo-bts,geosphere/osmo-bts,shimaore/osmo-bts,osmocom/osmo-bts,telenoobie/osmo-bts,osmocom/osmo-bts,telenoobie/osmo-bts,shimaore/osmo-bts,shimaore/osmo-bts,geosphere/osmo-bts,telenoobie/osmo-bts,telenoobie/osmo-bts,geosphere/osmo-bts