Invalid uplink mapping with multiple uplinks

[Vasily Gorin]

Steps to reproduce:

Scenario:
            1. Upload DVS plugin to the master node.
            2. Install plugin.
            3. Create cluster with vcenter.
            4. Create a new environment with following parameters:
                * Compute: KVM/QEMU with vCenter
                * Networking: Neutron with VLAN segmentation
                * Storage: default
                * Additional services: default
            5. Add nodes with following roles:
                * Controller
                * Compute
                * Compute
                * ComputeVMware
            6. Configure interfaces on nodes.
            7. Configure network settings.
            8. Enable VMware vCenter/ESXi datastore for images (Glance).
            9. Configure VMware vCenter Settings. Add 2 vSphere clusters and configure Nova Compute instances on controllers and compute-vmware.
            10. Enable and configure DVS plugin with multiple uplinks:
                  Cluster1:Cluster1:dvUplink1;dvUplink2;dvUplink3
                  Cluster2:Cluster2:dvUplink1;dvUplink2;dvUplink3
            11. Verify networks.
            12. Deploy cluster.
            13. Run OSTF.

Expected result:
  OSTF tests passed

Actual result:
  All vCenter OSTF tests were failed.

Part of dvs_agent log:

```
2016-09-22 13:14:52.214 768 CRITICAL neutron [req-02e7b087-a2bc-4ac9-9b61-5bf318cab8ed - - - - -] ValueError: Invalid uplink mapping: 'physnet2:dvUplink1;dvUplink2;dvUplink3'
2016-09-22 13:14:52.214 768 ERROR neutron Traceback (most recent call last):
2016-09-22 13:14:52.214 768 ERROR neutron File "/usr/bin/neutron-dvs-agent", line 10, in <module>
2016-09-22 13:14:52.214 768 ERROR neutron sys.exit(main())
2016-09-22 13:14:52.214 768 ERROR neutron File "/usr/lib/python2.7/dist-packages/networking_vsphere/agent/dvs_neutron_agent.py", line 426, in main
2016-09-22 13:14:52.214 768 ERROR neutron agent = DVSAgent(**agent_config)
2016-09-22 13:14:52.214 768 ERROR neutron File "/usr/lib/python2.7/dist-packages/networking_vsphere/agent/dvs_neutron_agent.py", line 86, in __init__
2016-09-22 13:14:52.214 768 ERROR neutron cfg.CONF.ML2_VMWARE, self.network_map)
2016-09-22 13:14:52.214 768 ERROR neutron File "/usr/lib/python2.7/dist-packages/networking_vsphere/utils/dvs_util.py", line 706, in create_uplink_map_from_config
2016-09-22 13:14:52.214 768 ERROR neutron raise ValueError("Invalid uplink mapping: '%s'" % mapping)
2016-09-22 13:14:52.214 768 ERROR neutron ValueError: Invalid uplink mapping: 'physnet2:dvUplink1;dvUplink2;dvUplink3'
```

[Igor Gajsin (igajsin)]

That's not a bug in the plugin. The vSphere cluster where it occured didn't have dvUplink3.