Merge branch 'virtio_mac'

Merge branch 'virtio_mac'

Amos Kong says:

====================
Currenly mac is programmed byte by byte. This means that we
have an intermediate step where mac is wrong.

Third patch introduced a new vq control command to set mac
address, it's atomic.

V2: check return of sending command, delay eth_mac_addr()
V3: restore software address when fail to set hardware address
V4: split eth_mac_addr, fix error handle
V5: rebase patches to net-next tree
====================

Signed-off-by: David S. Miller <davem@davemloft.net>