Multiple VLAN external network communication failed while using compute nodes.

Issue Scenario:

Multiple external VLAN flows are not getting created to forward packets between br-ex and br-int while adding external gateway to router.

Steps to reproduce the bug:

i) Used latest Boron distro from nexus repository.
ii) Once karaf UP stacked both control and compute nodes.
iii) Created external networks and router.
iv) Multiple external VLAN flows are not getting created once external gateway is attached to router.