openvswitch: Add support for network namespaces.

Following patch adds support for network namespace to openvswitch.
Since it must release devices when namespaces are destroyed, a
side effect of this patch is that the module no longer keeps a
refcount but instead cleans up any state when it is unloaded.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
diff --git a/net/openvswitch/vport-netdev.c b/net/openvswitch/vport-netdev.c
index 6ea3551..3c1e58b 100644
--- a/net/openvswitch/vport-netdev.c
+++ b/net/openvswitch/vport-netdev.c
@@ -83,7 +83,7 @@
 
 	netdev_vport = netdev_vport_priv(vport);
 
-	netdev_vport->dev = dev_get_by_name(&init_net, parms->name);
+	netdev_vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), parms->name);
 	if (!netdev_vport->dev) {
 		err = -ENODEV;
 		goto error_free_vport;