bsc: fixup for TC_cm_reestablishment: properly del MGCP ep

Fix SCCPlite run of TC_cm_reestablishment.

I'm not sure why it works for AoIP before this patch, but now it works
for both SCCPlite and AoIP.

Related: SYS#5130
Change-Id: I1c87272c5bb1ac452927054a9eef104d795e02f8

bsc/BSC_Tests.ttcn

@@ -9665,6 +9665,7 @@ private function f_tc_cm_reestablishment_1(charstring id) runs on MSC_ConnHdlr {
 	}
 	f_perform_clear()
 	f_expect_dlcx_conns();
+	f_create_mgcp_delete_ep(g_media.mgcp_ep);
 	COORD.send(REEST_CLEAR_DONE);
 }