ALSA: wss_lib: use struct snd_wss instead of snd_ad1848

The snd_wss is superset of the snd_ad1848 so kill
the latter and replace it with the snd_wss.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Reviewed-by: Rene Herman <rene.herman@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>