am335x: disable internal delay for RGMII mode

According to errata the AM335x device does not support internal delay
mode, so RGMII1_IDMODE and RGMII2_IDMODE must be set to 1.
Signed-off-by: NYegor Yefremov <yegorslists@googlemail.com>

board/ti/am335x/board.c

@@ -44,7 +44,7 @@ static struct uart_sys *uart_base = (struct uart_sys *)DEFAULT_UART_BASE;
 
 /* MII mode defines */
 #define MII_MODE_ENABLE		0x0
-#define RGMII_MODE_ENABLE	0xA
+#define RGMII_MODE_ENABLE	0x3A
 
 /* GPIO that controls power to DDR on EVM-SK */
 #define GPIO_DDR_VTT_EN		7