i40e: be more informative

If the VF sends a bad message, be more informative about what it
actually is.

Change-Id: I89e06d2db416a1d05aeea016dd6e8b7870cae99a
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>