Remove usage of deprecated get_ipv6_addr_by_EUI64 function
Remove usage of deprecated get_ipv6_addr_by_EUI64 function

As properly decorated with oslo-debtcollector, the get_ipv6_addr_by_EUI64
function from the data_utils module is deprecated. We should use the
equivalent function from oslo-utils instead.

Change-Id: Ida84f13fff2b660af67676ed3432ffefe0b8f2bb

masayukig/tempest,cisco-openstack/tempest,vedujoshi/tempest,openstack/tempest,Juniper/tempest,cisco-openstack/tempest,masayukig/tempest,openstack/tempest,vedujoshi/tempest,Juniper/tempest