MSC_Tests: Test what happens when the DLCX is dropped

Test the reaction of osmo-msc when the DLCX at the end of a call
is not answered. Normally osmo-msc should time out and clear the
connection.

Change-ID osmo-msc:I78f1b6a9149488a4ad3f120c1e190a83c07d4b89 fixes
a regression that causes osmo-msc to segfault due to a use after
free. This testcase provokes the situation that leads to the
crash.

Change-Id: Ic124ea116496209f9a1d8e74ae3e3a36cf866db0
Related OS#2881
Related OS#2882
2 files changed