[ALSA] via82xx: add __devinitdata

add __devinitdata to struct whitelist, since it's used within
a __devinit function.
Add const attribute to iterator variable, too.
Compile-tested (no section warnings etc.) and run-tested
on vt8233, 2.6.18-mm3 (hopefully applies well to current ALSA).

Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>