[mod_opus] FS ignores mono in conf and creates stereo channel

[admin-toneca]

Describe the bug
Freeswitch ignore param mono in opus.conf.xml for mono call and send stereo=1 in SDP to B-leg.

To Reproduce
Steps to reproduce the behavior:

1. Set mono in opus.conf.xml
   <param name="mono" value="1"/>
2. Set inbound-late-negotiation=true and inbound-codec-negotiation=generous
3. Send SDP in INVITE to A-leg:
   a=rtpmap:96 opus/48000/2
   a=fmtp:96 useinbandfec=1;maxaveragebitrate=64000; stereo=0; sprop-stereo=0
4. FreeSWITCH send to B-leg:
   a=rtpmap:102 opus/48000/2
   a=fmtp:102 useinbandfec=1; maxaveragebitrate=30000; maxplaybackrate=48000; ptime=20; minptime=10; maxptime=40; stereo=1

Expected behavior
FreeSWITCH should send INVITE to B-leg without stereo=1

Package version or git hash

• Version 1.10.9, 1.10.11

Trace logs
opus_log.txt