Fix two issues spotted by Sergei:
  - replace ENOMEM error value by ENOENT in ide-h8300 host driver
  - fix MODULE_PARM_DESC() in cmd640 host driver

Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>