[ALSA] hda-codec - Add test model for ALC268

This implements a test model for the ALC268.  It depends on the feature
added by alc260-test-eapd-0.2.diff.  This patch also adds a mention of
the ALC260 test model to ALSA-Configuration.txt since this seems to have
been missed.

Signed-off-by: Jonathan Woithe <jwoithe@physics.adelaide.edu.au>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt
index afdb6ff..22aee1a 100644
--- a/Documentation/sound/alsa/ALSA-Configuration.txt
+++ b/Documentation/sound/alsa/ALSA-Configuration.txt
@@ -801,6 +801,9 @@
 	  will		Will laptops (PB V7900)
 	  replacer	Replacer 672V
 	  basic		fixed pin assignment (old default model)
+	  test		for testing/debugging purpose, almost all controls can
+			adjusted.  Appearing only when compiled with
+			$CONFIG_SND_DEBUG=y
 	  auto		auto-config reading BIOS (default)
 
 	ALC262
@@ -821,6 +824,9 @@
 	  3stack	3-stack model
 	  toshiba	Toshiba A205
 	  acer		Acer laptops
+	  test		for testing/debugging purpose, almost all controls can
+			adjusted.  Appearing only when compiled with
+			$CONFIG_SND_DEBUG=y
 	  auto		auto-config reading BIOS (default)
 
 	ALC662