virtio-net: Introducing rxq and txq structs

Introducing rxq and txq structs representing the Rx and
Tx queues data correspondingly.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Reviewed-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
net: Added IFCAP_HWSTATS

Added IFCAP_HWSTATS iface capability indicating that
device driver and HW are capable to handle the statistics internally.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Reviewed-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
virtio-net: Collect statistics in virtio-net

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Reviewed-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
net: Added ifnet->if_get_if_info()

Added ifnet->if_get_if_info() method to collect the
internally gathered statistics into the standard if_data struct.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Reviewed-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
ifconfig: Fix issue #134

- Make ifconfig code use a new if_get_if_info()
  interface.
- Expanded the output of the ifconfig: exposed a few more
  statistics.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Reviewed-by: Asias He <asias@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>