ide-{floppy,tape,scsi}: fix register loading order when issuing packet command

Load IDE_BCOUNTL_REG before IDE_BCOUNTH_REG when issuing packet command.

It shouldn't affect anything (just a usual paranoia to separate changes
which change the way in which hardware is accessed from code cleanups).

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>