ALSA: hda - Add missing DMUX initialization for auto-mic with STAC/IDT

Added the missing initialization of DMUX connection (to analog input)
for auto-mic mode with STAC/IDT codecs.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/patch_sigmatel.c b/sound/pci/hda/patch_sigmatel.c
index abc44db..2405f841 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -4359,6 +4359,9 @@
 			stac_toggle_power_map(codec, cfg->hp_pins[i], 1);
 	}
 	if (spec->auto_mic) {
+		/* initialize connection to analog input */
+		snd_hda_codec_write_cache(codec, spec->dmux_nids[0], 0,
+					  AC_VERB_SET_CONNECT_SEL, 0);
 		if (enable_pin_detect(codec, spec->ext_mic.pin, STAC_MIC_EVENT))
 			stac_issue_unsol_event(codec, spec->ext_mic.pin);
 	}