PCI passthrough SRIOV support

Requements from SRIOV

• group device

  for SRIOV, alll VFs belong to same PF share same physical network reachability. so if you want, say, deploy a vlan network, you need choose the right PF's VF, otherwise network does not work for you.

• tracking device alloced to the NIC

  networking or other special deive is not as simple as pass though to the VM, there is need more configration. to acheive this, SRIOV must know the device infomation allocation to the specific NIC.

Solution: group the devices

whitlist alias use extra info (k,v) as group defination.

solution: tracking device allocated to alias

use request append infomation to alloced device then find if by (k,v)