ALSA: hda/conexant - Fix loopback issue with CX20632

On a machine with CX20632, Alsamixer doesn't have 'Loopback
Mixing' and 'Line'.

Signed-off-by: huangwenhui <huangwenhuia@uniontech.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220607065631.10708-1-huangwenhuia@uniontech.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>