liquidio: Configure switchdev with devlink

Enable and disable switchdev on SRIOV capable LiquidIO NIC with devlink.
Create representor netdev for each SRIOV VF function on SRIOV enable and
and do the cleanup on SRIOV disable.

Signed-off-by: Vijaya Mohan Guvva <vijaya.guvva@cavium.com>
Signed-off-by: Satanand Burla <satananda.burla@cavium.com>
Signed-off-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>