Fixed issue on configuring private_address on cp nodes

There is a problem on configuring private/public address/interface specifically
on compute nodes from hiera data, as during the deployment, the address of
physical interface will be assigned to vhost0.

Added a function to get various details of first interface which has any IP
assigned out of a provided list, or from interfaces fact. Used this function to
assign vncserver_proxyclient_address to make novnc work.