[PATCH 4.4 49/53] ASoC: rsnd: dont call update callback if it was NULL

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

commit d7289565483c65094d0473555625a4acd89567d3 upstream.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thong Ho <redacted>
Signed-off-by: Nhan Nguyen <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 sound/soc/sh/rcar/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c

@@ -1016,7 +1016,7 @@ static int rsnd_kctrl_put(struct snd_kco
 		}
 	}
 
-	if (change)
+	if (change && cfg->update)
 		cfg->update(cfg->io, mod);
 
 	return change;