This configuration parameter for the ML2/OVS agent was added in
I14fefe289a19b718b247bf0740ca9bc47f8903f4 and backported up to
stable/queens, preventing flooding on integration bridge in some cases.
It needs to be enabled on specific node types, so add option to
configure it.
Related-Bug: #1732067
Change-Id: Iff50d2d086c687ef9ec1ba878e24c06dfc8a7d99