VSD-domain type L2-DOMAIN-IRB

L2-DOMAIN-IRB VSD-domains are associated with R-VPLS services configured without a static route-target and vxlan VNI. VSD configures the dynamic route-target and VNI in the router VPLS service. The same considerations described for L2-DOMAINs apply to L2-DOMAIN-IRB domains with one exception: allow-ip-int-bind is now allowed.