Use ENODEV when the hdaps hardware isn't there, not ENXIO.

Cc: Jean Delvare <khali@linux-fr.org>
Cc: Robert Love <rml@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>