RAN_Emulation: allow sending UnitData from MSC_ConnHdlr

Add BSSAP_N_UNITDATA_req to RAN_Conn_PT, so that we are able to send a Paging
from a test function that runs on MSC_ConnHdlr.

This will be needed by upcoming MSC pool tests, see
I21cbab193cd0de2e5692665442eae113d5f61904.

Change-Id: I36d486db05169b0fc3f19112b5a9008248d62930
1 file changed