BA-IND in neighbor lists is not different on SI2xxx and SI5xxx
Each SI2xxx and SI5xxx type message contains a BA-IND flag that can be 0 or 1. In our case,
it's typically 0, except fro SI2quater, where it is 1.
When a MS sends measurement reports, it can indicate to which BA-IND the report belongs. This is commonly used to differentiate between reports against neighbor lists communicated on BCCH (SI2xxx) and reports against neighbor lists communicated on SACCH (SI5xxx).
Let's make sure we set all SI2xxx BA-IND to 0 and all SI5xxx BA-IND to 1 to facilitate this behavior.
Make sure BA-IND in all SI2xxx is '0' and in all SI5xxx is '1'
In masurement reports sent by the MS, this can then be used to correlate
if a given measurement report was in response to a BCCH/neighbor list
received on BCCH (SI2xxx) or on dowlink SACCH (SI5xxx).
gsm0408_test: Verify that BA-IND is 0 in SI2xxx and 1 in SI5xxx
This adds a test case to explicitly verify the BA-IND is as expected
by the behaviour introduced in Change-Id I1cd0dc51026dcd0e508e63eea4e333e6b184787a