ipv6: always put explicit interface field, even for default (0) interface

lib/refrepo/input_loader.rb

@@ -169,11 +169,7 @@ def add_ipv6(h)
             ip6 += '%x' % h['ipv6']['site_indexes'][site_uid]
             ip6 += '00:'
             ip6 += '%x' % ((ip4.split('.')[2].to_i & 0b1111) + 1)
-            if idx > 0
-              ip6 += ':%x::' % idx
-            else
-              ip6 += '::'
-            end
+            ip6 += ':%x::' % idx
             ip6 += '%x' % (ip4.split('.')[3].to_i)
             nah['ip6'] = ip6
           end
@@ -222,11 +218,7 @@ def add_kavlan_ipv6s(h)
               else
                 ip6 += '%x' % ((ip4.split('.')[2].to_i & 0b1111) + 1)
               end
-              if idx > 0
-                ip6 += ':%x::' % idx
-              else
-                ip6 += '::'
-              end
+              ip6 += ':%x::' % idx
               ip6 += '%x' % (ip4.split('.')[3].to_i)
               hn['kavlan6'][iface]["kavlan-#{kvl_id}"] = ip6
             end