ALSA: via82xx: add option to disable 500ms delay in snd_via82xx_codec_wait

There's a large 500ms delay in snd_via82xx_codec_wait() that, at least
on my hardware, appears to be unnecessary. The rest of the init of
the card works without logging any warnings or errors and both audio
and mixer settings work.

This adds an "nodelay" parameter to disable this (undocumented in the
code) large delay improving bootup time by 489-500ms.

[    1.034217] initcall alsa_card_via82xx_init+0x0/0x16 returned 0 after 505757 usecs
vs.
[    0.533136] initcall alsa_card_via82xx_init+0x0/0x16 returned 0 after 15915 usecs

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>