ipvs: try also real server with port 0 in backup server

	We should not forget to try for real server with port 0
in the backup server when processing the sync message. We should
do it in all cases because the backup server can use different
forwarding method.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>