Commit
23140d6f94ecc0e7cc9e1dc2372efdcaa97b15fe
by Neels Hofmeyr
mgcp_test.c: verify osmo-mgw accepts m=audio 0
When osmo-hnbgw does not yet know the remote port, it wants to send a CRCX to set up IuUP at the MGW, with the audio port set to zero. Make sure osmo-mgw accepts port == 0.