ide: mark "hdx=[driver_name]" and "hdx=scsi" kernel parameters as obsoleted

Mark "hdx=[driver_name]" and "hdx=scsi" kernel parameters as obsoleted
(nowadays device-driver binding can be changed at runtime through sysfs
 and it can also be dealt with using per device driver parameters).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>