Add support to implement HDMI/DP audio by using the common
snd-hda-codec-hdmi driver.

Change of codec driver affects user-space as the two
drivers expose different mixer controls. A new kernel
module option "use_common_hdmi" is added to user-space
to indicate which interface should be used. The default
driver can be selected via a Kconfig option.
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191029134017.18901-6-kai.vehmanen@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>