BTS_Tests.ttcn: add a test case for PTCCH/D and PTCCH/U

This test case is aimed to verify handling of both PTCCH/U and
PTCCH/D logical channels, recently implemented in [1]. This is
done by sending 16 Access Bursts on PTCCH/U, and then by
sending a random data block on PTCCH/D.

The existing TC_pcu_data_req_ptcch does not cover PTCCH/U, and
moreover involves TBF handling which has nothing to do with
PTCCH. Let's keep it anyway.

[1] I232e5f514fbad2c51daaa59ff516004aba97c8a3

Change-Id: I011ffdfa63b698ce6085968d15ffb4ff4bd23ee5
Related: OS#4102
2 files changed