ASoC: rsnd: fixup clkout_name[] index error for single AUDIO_CLKOUT SoC

2a46db4a3("ASoC: rsnd: add AUDIO_CLKOUT support") added AUDIO_CLKOUT
support for ADG. But single AUDIO_CLKOUT needs clkout_name[CLKOUT],
not clkout_name[i]. Kernel will have NULL pointer access without this
patch.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sh/rcar/adg.c

@@ -532,7 +532,7 @@ static void rsnd_adg_get_clkout(struct rsnd_priv *priv,
 	 * for clkout
 	 */
 	if (!count) {
-		clk = clk_register_fixed_rate(dev, clkout_name[i],
+		clk = clk_register_fixed_rate(dev, clkout_name[CLKOUT],
 					      parent_clk_name,
 					      (parent_clk_name) ?
 					      0 : CLK_IS_ROOT, req_rate);