ALSA: hda/realtek - Can't adjust speaker's volume on a Dell AIO

We have a Dell AIO on which we can't adjust its speaker's volume.
The problem is it is connected to a Audio Output node without Amp-out
capability. To fix it, we change it to be connnected to a node with
Amp-out capability.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>