mx53ard: Use IMX_GPIO_NR macro

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/board/freescale/mx53ard/mx53ard.c b/board/freescale/mx53ard/mx53ard.c
index 2d21584..01eca81 100644
--- a/board/freescale/mx53ard/mx53ard.c
+++ b/board/freescale/mx53ard/mx53ard.c
@@ -33,7 +33,7 @@
 #include <fsl_esdhc.h>
 #include <asm/gpio.h>
 
-#define ETHERNET_INT		(1 * 32 + 31)  /* GPIO2_31 */
+#define ETHERNET_INT		IMX_GPIO_NR(2, 31)
 
 DECLARE_GLOBAL_DATA_PTR;