duplicate multicast packets are reaching vm after sending igmp join

[vimal]

Duplicate multicast packets are reaching vm after sending igmp join . Contrail command is used to configure qfx10k as dc-gateway . On adding configs "set protocols igmp-snooping vlan bd-400 proxy" this issue is not seen.

topology
----------
Igmp join is sent from all 3 computes.

contrail---------------qfx10k--------source
  |
compute1(vm1) compute2(vm2) compute3(vm3)

Steps:
----------
Spawn 3 vm , one in each compute. Send igmp join from 3 VM.

For each multicast packet sent from source , VM1 will get 3 copy.

build
-------

ocata-master-414