dmaengine: mxs: Constify platform_device_id

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/mxs-dma.c

@@ -170,7 +170,7 @@ static struct mxs_dma_type mxs_dma_types[] = {
 	}
 };
 
-static struct platform_device_id mxs_dma_ids[] = {
+static const struct platform_device_id mxs_dma_ids[] = {
 	{
 		.name = "imx23-dma-apbh",
 		.driver_data = (kernel_ulong_t) &mxs_dma_types[0],