ASoC: Staticise asoc_idma_platform

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Sangbeom Kim <sbkim73@samsung.com>
diff --git a/sound/soc/samsung/idma.c b/sound/soc/samsung/idma.c
index baf97eb..2bcf758 100644
--- a/sound/soc/samsung/idma.c
+++ b/sound/soc/samsung/idma.c
@@ -410,7 +410,7 @@
 	idma.lp_tx_addr = addr;
 }
 
-struct snd_soc_platform_driver asoc_idma_platform = {
+static struct snd_soc_platform_driver asoc_idma_platform = {
 	.ops = &idma_ops,
 	.pcm_new = idma_new,
 	.pcm_free = idma_free,