mgcp_test: extend / rewrite test_mgcp_codec_pt_translate()

Instead of manually entering codec values, use mgcp_codec_add() to populate
test conns with codecs. The idea is to better test what actually happens when
parsing SDP codec strings.

Rewrite current test_mgcp_codec_pt_translate() from procedural to a data model
with human readable stdout logging.

This prepares to enable interpreting codec strings like "FOO/8000/1" as
equivalent with "FOO/8000": the SDP standard defines the final "/1", indicating
the nr of channels, as optional for a single channel, but osmo-mgw currently is
unable to match these two formats as identical. So prepare the
test_mgcp_codec_pt_translate() so that upcoming patches can incorporate strings
with and without the final "/1" by extending the struct arrays.

Change-Id: I888000d77512cfecb0f199b86ef6003e7fc0e6cb
2 files changed