bsc: TC_ho_in_fail_mgw_mdcx_timeout: fixup

Fix that the test was torn down too early, before DLCX messages were
received from OsmoBSC. This caused a race condition that sometimes
failed the test with:

VirtMGW-MGCP-0(1996)@e5a096d6b4ff: Dynamic test case error: Sending data on the connection of port MGCP_CLIENT to 1999:MGCP failed. (Broken pipe)

Related: OS#5787
Fixes: 7a8594a8 ("bsc: TC_ho_in_fail_mgw_mdcx_timeout: new test")
Change-Id: If47fa3e0204ce841c79a67dd78a1c53d04e4a586
1 file changed