[SCSI] u14-34f: fix data direction bug

Direction of data transfer 'DMA_FROM_DEVICE' was tested twice. DTD_OUT
means  transfer from host to device. This should occur when the
direction of data transfer (sc_data_direction) is 'DMA_TO_DEVICE'.

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>