[ALSA] via82xx: tweak VT8251 workaround

Move the workaround for the VT8251 up a bit, and check for STAT_EOL
rather than STAT_ACTIVE. This resolves issues some people were having
with certain ALSA clients (and allows the STAT_ACTIVE check to do what
it was intended to do).
This change was suggested by Andrew Daviel.

Signed-off-by: Bastiaan Jacques <b.jacques@planet.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>