libosmocore/BSC/MSC: MO voice calls rejected from Siemens S11E (patch included)

Hi,

I had a problem placing MO GSM calls from a Siemens S11E: The calls were dropped immediately; Osmo-MSC reports "Cannot compose Channel Type from bearer capabilities"

After investigating the SETUP request from the S11E, the phone does not use octet 3a (no extension bit set in IE 3). Wireshark decodes the radio channel requirement as "Full rate support only MS/fullrate speech version 1 supported", so I added a condition to the gsm48_ie.c function of libosmocore to include at least GSM FR in the list of available speech_ver in case octet 3 has no extension.

Attached to this message are the Abis-IP PCAP traces of MO calls, and the patch for gsm48_ie.c.

Regards, Lennart