net/vdev_netvsc: fix routed devices probing

net/vdev_netvsc: fix routed devices probing

NetVSC netdevices which are already routed should not be probed because
they are used for management purposes by the HyperV.

The corrupted code got the routed devices from the system file
/proc/net/route and wrongly parsed only the odd lines, so devices which
their routes were in even lines, were considered as unrouted devices
and were probed.

Use linux netlink lib to detect the routed NetVSC devices instead of
file parsing.

Fixes: 31182fadfb21 ("net/vdev_netvsc: skip routed netvsc probing")
Cc: stable@dpdk.org
Suggested-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Matan Azrad <matan@mellanox.com>