If you have two scheduled queues with the same mx_list and then one of
those domains is updated to use a different mx_list, depending on the
ordering of the updates and subsequent traffic, the changed domain may
continue to have traffic route through the old mx_list.
The reason for this is that protocol configuration for that egress path
comes from the scheduled queue configuration, and there is no explicit
dependency between the two pieces of configuration.
This commit resolves this by adding a sanity check that the protocol
information is consistent with the ready queue instance. If it is no
longer consistent we'll remove the association between the rq name and
the instance, then wind down any associated dispatchers.
Wez Furlong