CLOUDSTACK-10252: Delete dnsmasq leases file on restart (#2427)

Delete dnsmasq's leases file when dnsmasq is restarted to avoid it
use old ip-mac-address-vm mapping leases.

Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>

Author: yadvr

systemvm/debian/opt/cloud/bin/cs/CsDhcp.py

@@ -49,15 +49,21 @@ def process(self):
             self.add(self.dbag[item])
         self.write_hosts()
 
-        if self.cloud.is_changed():
-            self.delete_leases()
-
         self.configure_server()
 
-        restart_dnsmasq = self.conf.commit()
-        self.cloud.commit()
+        restart_dnsmasq = False
+
+        if self.conf.commit():
+            restart_dnsmasq = True
+
+        if self.cloud.commit():
+            restart_dnsmasq = True
+
         self.dhcp_opts.commit()
 
+        if restart_dnsmasq:
+            self.delete_leases()
+
         if not self.cl.is_redundant() or self.cl.is_master():
             if restart_dnsmasq:
                 CsHelper.service("dnsmasq", "restart")