Domain conf: allow more than one IP address for net devices

Add the possibility to have more than one IP address configured for a
domain network interface. IP addresses can also have a prefix to define
the corresponding netmask.

tests/lxcxml2xmldata/lxc-idmap.xml

@@ -28,6 +28,8 @@
     <interface type='bridge'>
       <mac address='00:16:3e:0f:ef:8a'/>
       <source bridge='bri0'/>
+      <ip address='192.168.122.12' family='ipv4' prefix='24'/>
+      <ip address='192.168.122.13' family='ipv4' prefix='24'/>
       <target dev='veth0'/>
       <guest dev='eth2'/>
     </interface>

tests/openvzutilstest.c

@@ -93,7 +93,7 @@ testReadNetworkConf(const void *data ATTRIBUTE_UNUSED)
         "  <devices>\n"
         "    <interface type='ethernet'>\n"
         "      <mac address='00:00:00:00:00:00'/>\n"
-        "      <ip address='194.44.18.88'/>\n"
+        "      <ip address='194.44.18.88' family='ipv4'/>\n"
         "    </interface>\n"
         "    <interface type='bridge'>\n"
         "      <mac address='00:18:51:c1:05:ee'/>\n"

tests/sexpr2xmldata/sexpr2xml-bridge-ipaddr.xml

@@ -24,7 +24,7 @@
     <interface type='bridge'>
       <mac address='00:11:22:33:44:55'/>
       <source bridge='xenbr2'/>
-      <ip address='192.0.2.1'/>
+      <ip address='192.0.2.1' family='ipv4'/>
       <script path='vif-bridge'/>
       <target dev='vif6.0'/>
     </interface>

tests/sexpr2xmldata/sexpr2xml-net-routed.xml

@@ -23,7 +23,7 @@
     </disk>
     <interface type='ethernet'>
       <mac address='00:11:22:33:44:55'/>
-      <ip address='172.14.5.6'/>
+      <ip address='172.14.5.6' family='ipv4'/>
       <script path='vif-routed'/>
       <target dev='vif6.0'/>
     </interface>