Optimize empty loadbalancer page

do not ask for list of floating IPs if there's no LBs,
no need for (potentially costly) API calls
when the result will be thrown out anyway.

Change-Id: I9a7f72fa8f95fe56a95216b72f7c1d7542cfcbcc
Signed-off-by: Pavlo Shchelokovskyy <shchelokovskyy@gmail.com>

octavia_dashboard/api/rest/lbaasv2.py

@@ -696,6 +696,8 @@ def add_floating_ip_info(request, loadbalancers):
     """Add floating IP address info to each load balancer.
 
     """
+    if not loadbalancers:
+        return
     floating_ips = neutron.tenant_floating_ip_list(request)
     for lb in loadbalancers:
         floating_ip = {}