RRD graphs are not created correctly for interfaces using CODELQ
If a user sets an interface queue to CODELQ, errors appear in the logs from RRD:
RRD create failed exited with 1, the error is: ERROR: you must define at least one Data Source
The command '/usr/bin/nice -n20 /usr/local/bin/rrdtool update /var/db/rrd/opt4-queues.rrd -t N' returned exit code '1', the output was 'ERROR: Not enough arguments'
When CODELQ is set on an interface, it has no child queues, which may be the source of the problem.