The leaf qos is deprecated with status deprecated in the model and it was replaced by the list qos-entry.

in the 'list queue-list' there is a 'leaf queue-uuid' which is deprecated.This is replaced by 'leaf queue-ref'.
Remove leaf qos,leaf queue-uuid from the model and then to remove the relevant code in the ovsdb plugin that supports these two model elements. For backward compatibility, the code still supports these two things.

Resolution:
https://git.opendaylight.org/gerrit/#/c/50151/