msc: Expect CommonID from MSC by default

As of osmo-msc Change-Id I2552736477663adb250c55728093500e8ae83ebb,
osmo-msc is always sending BSSMAP CommonID to the BSC.  Let's adjust our
test expectation, while allowing the user to start the tests with
BSC_ConnectionHandler.mp_expect_common_id := false
to get the existing behavior (expect no bSSMAP CommonId) can be
restored, e.g. for testing 'latest'.

Change-Id: I4976d9bb1f07c8ab4ffa02848414f8ddd1bdfd3f
Related: OS#2969
2 files changed