ALSA: hda - add support for HD-Audio of VIA HDMI GFX Cards

This is patch supporting HD-Audio function of VIA GFX cards which
support HDMI.
Those are integrated graphics of chipsets VX900 and VX11 separately.

Signed-off-by: Annie Liu <annieliu@viatech.com.cn>
Signed-off-by: Takashi Iwai <tiwai@suse.de>