Fix idempotence issue with agent install manifest

It is known that MidoNet agent conflicts with openvswitch-switch service,
the two can not co-exist. Agent manifest already purges the package
providing the openvswitch service which results in service being stopped,
we do not need to explicitly call service class (which BTW breaks compute
re-deploy, when package is alredy uninstalled)

Change-Id: I6b11790d013072dc9dcfaa32a278793834c8e2c8

deployment_scripts/puppet/manifests/midonet-install-agent.pp

@@ -42,11 +42,6 @@ $openvswitch_package = $operatingsystem ? {
   'Ubuntu' => 'openvswitch-switch'
 }
 
-service {$ovsdb_service_name:
-  ensure => stopped,
-  enable => false
-} ->
-
 package {$openvswitch_package_neutron:
   ensure => purged
 } ->