Ports polling issue for Huawei NE20 routers

Hi Adam/Team.

I recently upgraded to SVN revision 9233 and saw there are some Huawei related improvements in the SVN log. 

For the basic AR routers all still works great, but since the update, Observium can't pull any information about ports from NE20 higher-end devices. All existing ports have been deleted and the ports page is now blank on those devices.

I've looked a the discovery and poller debug output, but it seems that Observium is not getting a response anymore as per the discovery module output below.

Prior to upgrade this had been fine for years.

Any ideas on how to resolve this? Happy to provide logs/testing and whatever else would assist.

##### Module Start: ports ##### o Caching OIDs ifDescr CMD[/usr/bin/snmpbulkwalk -Cr100 -t '3' -r '5' -v2c -c *** -Pu -OQUs -m IF-MIB -M /opt/observium/mibs/rfc:/opt/observium/mibs/net-snmp 'udp':'fc_transit1_thn':'161' ifDescr]

CMD EXITCODE[1]

CMD RUNTIME[18.027s]

STDOUT[]

STDERR

[Timeout: No Response from udp:fc_transit1_thn:161]SNMP STATUS[FALSE]SNMP ERROR[#1002 - Request timeout]