i40evf: remove dead code

The only error case is when the malloc fails, in which case the clean up
loop does nothing at all, so remove it

Signed-off-by: Alan Cox <alan@linux.intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>