[ALSA] Add ASUS Z71V support

Documentation,HDA Codec driver
Added the ASUS Z71V (or similar) laptop support.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

Documentation/sound/alsa/ALSA-Configuration.txt

@@ -636,6 +636,7 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed.
 	  5stack	5-jack in back, 2-jack in front
 	  5stack-digout	5-jack in back, 2-jack in front, a SPDIF out
 	  w810		3-jack
+	  z71v		3-jack (HP shared SPDIF)
 
 	CMI9880
 	  minimal	3-jack in back