ALSA: wss-lib: move AD1845 frequency setting into wss-lib

This is required to allow the sscape driver
to autodetect installed codec.

Also, do not create a timer if detected codec
has no hardware timer (e.g. AD1848).

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Rene Herman
Signed-off-by: Takashi Iwai <tiwai@suse.de>