ASoC: fsl_sai: Drop useless ret in startup()

We can save this ret to make the code neater.
Signed-off-by: Nicolin Chen <Guangyu.Chen@freescale.com>
Reviewed-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/fsl/fsl_sai.c

@@ -334,12 +334,9 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
 static int fsl_sai_startup(struct snd_pcm_substream *substream,
 		struct snd_soc_dai *cpu_dai)
 {
-	int ret;
 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
 
-	ret = clk_prepare_enable(sai->clk);
-
-	return ret;
+	return clk_prepare_enable(sai->clk);
 }
 
 static void fsl_sai_shutdown(struct snd_pcm_substream *substream,