bsc: as_Media_mgw: fail on DLCX

as_Media_mgw() is used to establish a voice stream. If a DLCX happens as
part of that, that should be flagged as a problem.

In fact the Mode Modify test with current osmo-bsc does exhibit a DLCX
right upon the Assignment Complete message, which is a bug fixed in
I5ab10ee7fd9c5d7608e8a06893881d990943feed.

This patch now correctly flags this as a failure.

In the two tests
TC_ho_in_fail_no_detect, TC_ho_in_fail_no_detect2
the expected failure causes expected DLCX, so exempt those.

Related: SYS#5916
Change-Id: I0633f60f09d58802f6be0238ef41a632d93a4327
2 files changed