ALSA: Document tyan model for Realtek ALC262

As just pointed out to me, the new tyan model for ALC262 was
implemented but not documented. This adds the board to the
list, using both its marketing name (Thunder n6650W) and its
model number (S2915-E).
Signed-off-by: NTony Vroon <tony@linx.net>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Documentation/sound/alsa/HD-Audio-Models.txt

@@ -56,6 +56,7 @@ ALC262
   sony-assamd	Sony ASSAMD
   toshiba-s06	Toshiba S06
   toshiba-rx1	Toshiba RX1
+  tyan		Tyan Thunder n6650W (S2915-E)
   ultra		Samsung Q1 Ultra Vista model
   lenovo-3000	Lenovo 3000 y410
   nec		NEC Versa S9100