ALSA: ALSA: hda - Fix ALC883 medion model

ALC883 medion model doesn't unmute the proper amps so no output can be heard.
Replaced the mute switches to behave just like other models.

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