ASoC: sigmadsp: fix simple_return.cocci warnings

sound/soc/codecs/sigmadsp.c:656:1-4: WARNING: end returns can be simpified and declaration on line 636 can be dropped

Simplify a trivial if-return sequence. Possibly combine with a
preceding function call.
Generated by: scripts/coccinelle/misc/simple_return.cocci

Signed-off-by: Fengguang Wu <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/sigmadsp.c

···
 {
 	struct snd_kcontrol_new template;
 	struct snd_kcontrol *kcontrol;
-	int ret;
 
 	memset(&template, 0, sizeof(template));
 	template.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
···
 	kcontrol->private_free = sigmadsp_control_free;
 	ctrl->kcontrol = kcontrol;
 
-	ret = snd_ctl_add(sigmadsp->component->card->snd_card, kcontrol);
-	if (ret)
-		return ret;
-
-	return 0;
+	return snd_ctl_add(sigmadsp->component->card->snd_card, kcontrol);
 }
 
 static void sigmadsp_activate_ctrl(struct sigmadsp *sigmadsp,