ixgbe: Add SR-IOV register, structure and bit defines

This patch adds register definitions, bit definitions and structures used by
the driver to support SR-IOV features of the 82599 controller.

Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>