interface: Allow VLAN tag-rewrite on non-sub-interfaces too.

This fix was first made in
    commit fdea5c6a00b74971dbb1b7ec4e25839a871006ca
but was subsequently lost in
    commit 053204ab039d34a990ff0e14c32ce3b294fcce0e

Added unit test for setting VTR on a non-sub-interface to
help ensure no future regressions of this ability.

Type: fix
Change-Id: I71ce2684fb72383741455829ae2d397ea2e95eae
Signed-off-by: Jon Loeliger <jdl@netgate.com>
diff --git a/src/vnet/interface.api b/src/vnet/interface.api
index efc5bb4..39bb9ca 100644
--- a/src/vnet/interface.api
+++ b/src/vnet/interface.api
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-option version = "3.2.1";
+option version = "3.2.2";
 
 import "vnet/interface_types.api";
 import "vnet/ethernet/ethernet_types.api";