i40e/i40evf: give up the __func__

During early development, we added the function name to all of the error
strings to make debugging simpler. Now that we've released the driver,
our users should have more comprehensible error messages. So tear the
roof off and give up the __func__. Ow.

Change-ID: I7e1766252c7a032b9af6520da6aff536bdfd533c
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>