Changes

asterisk: Rework test TC_ims_call_mo_after_tcp_conn_closed with new expectancies

Previous expected behavior (and Asterisk-UE implementation) was wrong.
Since recently, Asterisk behaves better, that is, whenever the TCP conn
is dropped by the peer, it will attempt re-connecting and
re-registering.

Related: SYS#7398
Change-Id: I7ec1e8e30c4d72be96c8e300e0d038e63ba0e600