[ovn] Don't add conntrack entries for Geneve
[ovn] Don't add conntrack entries for Geneve

As Geneve UDP traffic is allowed, there's no reason to create
conntrack entries as it may result in a performance hit.

This patch is preventing Geneve traffic to be sent to conntrack.

Closes-Bug: #1885551
Change-Id: I1eb6c77ea3cbdfaaa2b2a3fec0e6b8d2a71aae95
Signed-off-by: Daniel Alvarez <392af6018b88c256f4a2770258d802fccb5f3af6@redhat.com>

openstack/tripleo-heat-templates,openstack/tripleo-heat-templates