ALSA: usb-audio: Fix format string mismatch in mixer.c

Fix format string mismatch in parse_audio_selector_unit().
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer.c

@@ -1986,7 +1986,7 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid, void
 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
 			len = get_term_name(state, &iterm, namelist[i], MAX_ITEM_NAME_LEN, 0);
 		if (! len)
-			sprintf(namelist[i], "Input %d", i);
+			sprintf(namelist[i], "Input %u", i);
 	}
 
 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);