upon emergency call, from the MSC-pool pick an MSC that allows emergency calling
In the presence of an MSC pool in osmo-bsc, we pick an MSC based on TMSI or round-robin.
If only some of the MSC allow an emergency call (msc / allow-emergency (allow|deny))
we could influence the choice of MSC based on the CHREQ reason being "emergency call".
I'm not sure that this has real world relevance, guessing that normally either all or
none of the MSC allow emergency calling.