ALSA: hda - initialize node 0x21 properly on AD1988 codecs

The widget node 0x21 should be initialized as unmuted/full (0dB)
as default.  This will reduce additional manual work by user at the
first time use.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

sound/pci/hda/patch_analog.c

@@ -2207,6 +2207,8 @@ static struct hda_verb ad1988_6stack_init_verbs[] = {
 	{0x34, AC_VERB_SET_CONNECT_SEL, 0x0},
 	/* Analog CD Input */
 	{0x18, AC_VERB_SET_PIN_WIDGET_CONTROL, PIN_IN},
+	/* Analog Mix output amp */
+	{0x21, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_UNMUTE | 0x1f}, /* 0dB */
 
 	{ }
 };
@@ -2336,6 +2338,8 @@ static struct hda_verb ad1988_3stack_init_verbs[] = {
 	{0x08, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
 	{0x09, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
 	{0x0f, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
+	/* Analog Mix output amp */
+	{0x21, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_UNMUTE | 0x1f}, /* 0dB */
 	{ }
 };
 
@@ -2409,6 +2413,8 @@ static struct hda_verb ad1988_laptop_init_verbs[] = {
 	{0x08, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
 	{0x09, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
 	{0x0f, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_MUTE},
+	/* Analog Mix output amp */
+	{0x21, AC_VERB_SET_AMP_GAIN_MUTE, AMP_OUT_UNMUTE | 0x1f}, /* 0dB */
 	{ }
 };