DHCP issue on the second ONU, when two ONUs exists on the same PON port

Problem:

DHCP fails to succeed on the second ONU after auth+dhcp+ping succeed on the first ONU. These two ONUs exist on the same PON port. But, the third ONU on a different pon port, authentication goes through fine along with subscriber addition and DHCP/pings worked fine.

Steps to Reproduce:

• Peform authentication on the first ONU
• Perform volt-add-subscriber-access on the first ONU
• Perform DHCP on the first ONU which succeeds (pings also succeed)
• Perform authentication on the second ONU which succeeds
• perform "volt-add-subscriber-access" call on the second ONU that succeeds
• Perform DHCP, which fails with an error 

Errors in ONOS

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2019-12-09 09:03:17,925 | INFO  | .233.75.24:43458 | DhcpL2Relay                      | 182 - org.opencord.dhcpl2relay-app - 1.6.1 | Received DHCP Packet of type DHCPOFFER from of:0000b86a974385f7/10485762019-12-09 09:03:17,929 | WARN  | .233.75.24:43458 | DhcpL2Relay                      | 182 - org.opencord.dhcpl2relay-app - 1.6.1 | Cannot determine host for DHCP client: B4:96:91:0C:4F:E4. Aborting relay for dhcp packet from server

• It was noticed that the DHCP DISCOVER packets took the dataplane path instead of being trapped to ONOS