drm/nouveau/kms: Fix regression by audio component transition

Since the commit 742db30c ("drm/nouveau: Add HD-audio component
notifier support"), the nouveau driver notifies and pokes the HD-audio
HPD and ELD via audio component, but this seems broken.  The culprit
is the naive assumption that crtc->index corresponds to the HDA pin.
Actually this rather corresponds to the MST dev_id (alias "pipe" in
the audio component framework) while the actual port number is given
from the output ior id number.

This patch corrects the assignment of port and dev_id arguments in the
audio component ops to recover from the HDMI/DP audio regression.

Fixes: 742db30c

 ("drm/nouveau: Add HD-audio component notifier support")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207223
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>