dmaengine: ep93xx: 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>
diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index 24e5290..57ff462 100644
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -1364,7 +1364,7 @@
 	return ret;
 }
 
-static struct platform_device_id ep93xx_dma_driver_ids[] = {
+static const struct platform_device_id ep93xx_dma_driver_ids[] = {
 	{ "ep93xx-dma-m2p", 0 },
 	{ "ep93xx-dma-m2m", 1 },
 	{ },