ALSA: hda - Add missing num_adc_nids definition for IDT92HD8xxx

The previous fix removed the definition of num_adc_nids wrongly, and
this resulted in the missing input-source control.  Now readded again.

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 7d33e0a..eb9ca6f7 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -5297,6 +5297,7 @@
 	spec->mux_nids = stac92hd83xxx_mux_nids;
 	spec->num_muxes = ARRAY_SIZE(stac92hd83xxx_mux_nids);
 	spec->adc_nids = stac92hd83xxx_adc_nids;
+	spec->num_adcs = ARRAY_SIZE(stac92hd83xxx_adc_nids);
 	spec->pwr_nids = stac92hd83xxx_pwr_nids;
 	spec->pwr_mapping = stac92hd83xxx_pwr_mapping;
 	spec->num_pwrs = ARRAY_SIZE(stac92hd83xxx_pwr_nids);