Currently, deploying a multi-node AIO results in
internal_lb_vip_address and external_lb_vip_address being set to the
same IP (10.0.236.150), which results in services having issues
communicating with the lb.
This commit simply sets external_lb_vip_address to use the
load balancer's dhcp address, which is fixed to 10.0.2.150.
Change-Id: I6faabd641c0559a0381e559f364cc76c49293014