ALSA: hda - Get back Input Source for ALC262 toshiba-s06 model

The commit f9e336f6
    ALSA: hda - Unify capture mixer creation in realtek codes
removed the "Input Source" mixer element creation for toshiba-s06 model
because it contains a digital-mic input.

This patch take the control back.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>

sound/pci/hda/patch_realtek.c

@@ -11539,6 +11539,7 @@ static struct alc_config_preset alc262_presets[] = {
 		.capsrc_nids = alc262_dmic_capsrc_nids,
 		.dac_nids = alc262_dac_nids,
 		.adc_nids = alc262_dmic_adc_nids, /* ADC0 */
+		.num_adc_nids = 1, /* single ADC */
 		.dig_out_nid = ALC262_DIGOUT_NID,
 		.num_channel_mode = ARRAY_SIZE(alc262_modes),
 		.channel_mode = alc262_modes,