The sata_dwc_qc_prep() does nothing.  Use the default ata_noop_qc_prep
instead.
Tested-by: NChristian Lamparter <chunkeey@googlemail.com>
Signed-off-by: NMans Rullgard <mans@mansr.com>
Signed-off-by: NTejun Heo <tj@kernel.org>