CLOUDSTACK-4132 current dnsmasq config does not allow guest virtual machines(clients) to update its hostnames with a DNS server

Introducing the option dhcp-client-update fails if the dnsmasq version is less than 2.6 (like in older templates).
Added a check for the version in cloud-early-config. will add dhcp-client-update option in the config file only
if the dnsmasq version is 2.6 and above.

Signed-off-by: Jayapal <jayapal@apache.org>

patches/systemvm/debian/config/etc/init.d/cloud-early-config

@@ -724,6 +724,15 @@ setup_dnsmasq() {
       then
        echo "$ETH0_IP6 data-server" >> /etc/hosts
   fi
+#add the dhcp-client-update only if dnsmasq version is 2.6 and above
+  dnsmasqVersion=$(dnsmasq -v |  grep version -m 1 | grep -o  "[[:digit:]]\.[[:digit:]]")
+  major=$(echo "$dnsmasqVersion" | cut -d '.' -f 1)
+  minor=$(echo "$dnsmasqVersion" | cut -d '.' -f 2)
+  if [ "$major" -eq '2' -a  "$minor" -ge '6' ] || [ "$major" -gt '2' ]
+  then
+      sed -i -e "/^dhcp-client-update/d" /etc/dnsmasq.conf
+      echo 'dhcp-client-update' >> /etc/dnsmasq.conf
+  fi
 }
 
 setup_sshd(){