VPN flows in Table 21 pointing to wrong DCGW

VPN flows in Table 21 pointing to wrong DCGW

Issue:
=====
VPN flows in Table 21 pointing to wrong DCGW and traffic fails for
affected flows

RCA:
=====
Observed conflicting modifications on the same flow when bgp driven and
vpn-footprint driven logic executed at the same time.
This fix introduces the DJC retry approach for vpn-footprint driven flow
programming logic.

Solution:
========
Have fixed the code logic to point the right DC-GW
output action for BGP advertised routes.

Change-Id: I54838ce701b1be6126b787ba08b712222463a71d
Signed-off-by: Karthikeyan Krishnan <karthikeyangceb007@gmail.com>