dm: scsi: Drop duplicate SCSI and DM_SCSI options

When the SATA code was moved into drivers/ata these Kconfig options were
added to that directory. They already exist in drivers/scsi. Remove them
from drivers/ata to fix the duplication.

Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 7f2b5f4 (sata: Move drivers into new drivers/ata directory)