ASoC: Staticise simtec_audio_resume()

It is exported via resume callback of struct dev_pm_ops rather than referenced
directly and so should be staticised.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/samsung/s3c24xx_simtec.c

@@ -300,7 +300,7 @@ static void detach_gpio_amp(struct s3c24xx_audio_simtec_pdata *pd)
 }
 
 #ifdef CONFIG_PM
-int simtec_audio_resume(struct device *dev)
+static int simtec_audio_resume(struct device *dev)
 {
 	simtec_call_startup(pdata);
 	return 0;