i40e: support VFs on PFs other than 0

i40e: support VFs on PFs other than 0

When communicating with VF devices over the AQ, the FW refers to the
VF by its global VF ID, not local the VF ID with reference to its
parent PF. Since the global and local VF IDs are identical for PF 0,
the code worked correctly on PF 0.

However, we cannot just use global IDs throughout the code as most of
the other references to the VF (VSI setup, register offsets, etc.)
require the local VF ID. Instead, we just add or subtract our base VF
ID when sending and receiving AQ messages.

Change-Id: I92f4332b4876bc68b2f9af9ebf48761f63b6bd97
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>