ASoC: rsnd: call missing snd_ctl_remove()

Current Renesas R-Car sound driver is using snd_ctl_xxx()
functions, but it didn't call snd_ctl free_one() / snd_ctl_remove().
This patch call these functions.

Reported-by: Nguyen Viet Dung <nv-dung@jinso.co.jp>
Reported-by: Bui Duc Phuc <bd-phuc@jinso.co.jp>
Reported-by: Cao Minh Hiep <cm-hiep@jinso.co.jp>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index f0bb137..6fb38b8 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -1046,14 +1046,23 @@
 		return -ENOMEM;
 
 	ret = snd_ctl_add(card, kctrl);
-	if (ret < 0)
+	if (ret < 0) {
+		snd_ctl_free_one(kctrl);
 		return ret;
+	}
 
 	cfg->update = update;
+	cfg->card = card;
+	cfg->kctrl = kctrl;
 
 	return 0;
 }
 
+void _rsnd_kctrl_remove(struct rsnd_kctrl_cfg *cfg)
+{
+	snd_ctl_remove(cfg->card, cfg->kctrl);
+}
+
 int rsnd_kctrl_new_m(struct rsnd_mod *mod,
 		     struct snd_soc_pcm_runtime *rtd,
 		     const unsigned char *name,