bsc: Look for CM Service Requests with emergency cause

Look for emergency calls and send them to a MSC that can
handle them properly.
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_msc.c b/openbsc/src/osmo-bsc/osmo_bsc_msc.c
index 617a59a..55532db 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_msc.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_msc.c
@@ -492,6 +492,7 @@
 	msc_data->rtp_base = 4000;
 
 	msc_data->nr = nr;
+	msc_data->allow_emerg = 1;
 
 	return msc_data;
 }