datapath-windows: Add support for NAT in conntrack

datapath-windows: Add support for NAT in conntrack

Add support for parsing netlink attributes related to NAT
in conntrack.

Co-Authored-by: Yin Lin <linyi@vmware.com>
Co-Authored-by: Darrell Ball <dlu998@gmail.com>
Signed-off-by: Anand Kumar <kumaranand@vmware.com>
Signed-off-by: Yin Lin <linyi@vmware.com>
Signed-off-by: Darrell Ball <dlu998@gmail.com>
Acked-by: Alin Gabriel Serdean <aserdean@cloudbasesolutions.com>
Signed-off-by: Gurucharan Shetty <guru@ovn.org>