freescale: remove incorrect copied comment

The comment in question is word-for-word copied from ixgbe, and clearly
has no meaning in freescale's driver. (it even says 'return an error'
when the code clearly does not). Remove the comment as it is obviously
incorrect and not applicable to the code as it is today.

CC: Pantelis Antoniou <pantelis.antoniou@gmail.com>
CC: Vitaly Bordug <vbordug@ru.mvista.com>
CC: <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>