Correct Neutron RabbitMQ User Param Mapping
Correct Neutron RabbitMQ User Param Mapping

Changed parameter mapping for RabbitMQ user name
overrides. THT maps the user name override to
neutron::rabbit_user for the Neutron service only.

This will allow the transport_url string to be built
correctly when a deployer wishes to override the default
guest username.

Change-Id: I0e35a6979765a453e2ed219e6026f6c0a17b2013
Closes-Bug: 1746034

openstack/puppet-tripleo,openstack/puppet-tripleo,openstack/puppet-tripleo