EVPN-VXLAN: Symmetric IRB routing with EVPN Route Type 2

This feature supports EVPN-VXLAN integrated routing and bridging (IRB) symmetric routing, based on EVPN Type 2 routes, where the lookup operation is symmetric at both ingress and egress PE devices. Both ingress and egress PE devices perform lookups on both MAC and IP addresses. The ingress PE device performs a MAC lookup followed by an IP lookup and the egress PE device performs an IP lookup followed by a MAC lookup.