ALSA: fm801: add error handling for snd_ctl_add

When snd_ctl_add fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling snd_ctl_add.
Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/fm801.c

@@ -1068,11 +1068,19 @@ static int snd_fm801_mixer(struct fm801 *chip)
 		if ((err = snd_ac97_mixer(chip->ac97_bus, &ac97, &chip->ac97_sec)) < 0)
 			return err;
 	}
-	for (i = 0; i < FM801_CONTROLS; i++)
-		snd_ctl_add(chip->card, snd_ctl_new1(&snd_fm801_controls[i], chip));
+	for (i = 0; i < FM801_CONTROLS; i++) {
+		err = snd_ctl_add(chip->card,
+			snd_ctl_new1(&snd_fm801_controls[i], chip));
+		if (err < 0)
+			return err;
+	}
 	if (chip->multichannel) {
-		for (i = 0; i < FM801_CONTROLS_MULTI; i++)
-			snd_ctl_add(chip->card, snd_ctl_new1(&snd_fm801_controls_multi[i], chip));
+		for (i = 0; i < FM801_CONTROLS_MULTI; i++) {
+			err = snd_ctl_add(chip->card,
+				snd_ctl_new1(&snd_fm801_controls_multi[i], chip));
+			if (err < 0)
+				return err;
+		}
 	}
 	return 0;
 }