ranap_parse_lai(): Fix wrong BCD decoding for MNC. Add test.

Fix the ranap_parse_lai() part that decodes the MNC: place the *10 at the
proper MNC digit.

Add a comprehensive test for ranap_parse_lai() in test-helpers.c. Because
ranap_parse_lai() logs things, add test_common.c to test-helpers compilation
and an expected stderr output to test-helpers' testsuite.at def.
6 files changed