Description of problem:

The Neutron arguments in the "openstack overcloud deploy" were marked as DEPRECATED in 11/15 with this change - https://review.openstack.org/#/c/226790/ - as they could be set in heat templates.

$ openstack overcloud deploy --help
...
  --neutron-disable-tunneling
                        Disables tunneling. (DEPRECATED)

This change in OSP10 - https://review.openstack.org/#/c/335235 - removed the use of NeutronEnableTunneling from heat templates and .pp files as it was redundant. 

The neutron-disable-tunneling argument is still in the UI however.  If a user
successfully used this argument to disable tunneling in OSP 8 or OSP 9 (even though
the argument was deprecated) and then upgraded to OSP 10 and used the same deploy command, tunneling would no longer be disabled.

Some possible ways to fix this:
1. If arg set, return an Error with a message along the lines "neutron-disable-tunneling has been deprecated, set NeutronTunnelTypes to '' and NeutronNetworkType in template files"  -OR-
2. If arg set, Silently set NeutronTunnelTypes to '' in python-tripleclient to force no tunneling.  -OR-
3. Remove neutron-disable-tunneling as a valid argument so that the deploy command fails and user will have to remove the argument


Version-Release number of selected component (if applicable):
OSP10

How reproducible:
Every time.

Steps to Reproduce:
1. Run "openstack overcloud deploy" with --neutron-disable-tunneling
2. Verify vxlan (by default) tunnel has been created

Actual results:
vxlan tunnel is created.


Expected results:
No tunnel created.

Additional info: