config 'msc' / 'core-location-area-code' is a non-feature
OsmoBSC seems to support setting an entire MSC on a forced Location Area Code (LAC).
The only place where this reflects is composing a CGI for an MSC (cgi_for_msc()), when sending a Create Layer 3 and Handover Performed to an MSC.
So an MSC is made to believe that a subscriber comes from a specific LAC.
The reverse direction will not work: when the MSC asks to Page a subscriber on the LAC it thinks the subscriber is camped on,
the BSC will likely not recognise this forced LAC from core-location-area-code, and not Page at all or on the wrong cell.
I also currently don't see how this can work, because overwriting a cell's LAC to the MSC is lossy and cannot be reversed.
The only solution I see is to Page on the entire BSS when an MSC has a forced LAC.
Either properly revive and test this feature, or I guess we can also drop it entirely.