ixgbe: add VF IPsec management

Add functions to translate VF IPsec offload add and delete requests
into something the existing code can work with.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>