ARM: SAMSUNG: Fix compiler warning in dma-ops.c file

Fixes the following build warning:
arch/arm/plat-samsung/dma-ops.c:129:2: warning: initialization from incompatible pointer type [enabled by default]
arch/arm/plat-samsung/dma-ops.c:129:2: warning: (near initialization for 'dmadev_ops.release') [enabled by default]
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/plat-samsung/dma-ops.c

@@ -36,8 +36,7 @@ static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
 	return (unsigned)dma_request_channel(mask, pl330_filter, filter_param);
 }
 
-static int samsung_dmadev_release(unsigned ch,
-			struct s3c2410_dma_client *client)
+static int samsung_dmadev_release(unsigned ch, void *param)
 {
 	dma_release_channel((struct dma_chan *)ch);