Use the new attribute 'port_type' of the vrouter thrift API

Change-Id: Icbcbe7bc6ef7a88c8f3a4aa11b36034e36dca0f5
(cherry picked from commit 1a9bdfa4ee6d5a004134649c21c7c8a75def7aa9)
Merge "Use the new attribute 'port_type' of the vrouter thrift API" into R1.10