Remove iproute dependency from vrouter package

Remove dependency and move the installation of the correct version
of iproute (1:3.10.0-1ubuntu1) in provisioning scripts. The updated
version is only needed when lbaas support is needed with haproxy.

Change-Id: I448b610a0bc2479b3ddcc39dedfe47b9f30b53f2
Closes-Bug: #1380836