board: sama5d2_xplained: Set 'ethaddr' got from AT24MAC

If 'ethaddr' is not set, we will get the ethernet address from AT24MAC,
and set it to 'ethaddr' variable.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Songjun Wu <songjun.wu@microchip.com>
Reviewed-by: Andreas Bießmann <biessmann@corscience.de>
diff --git a/include/configs/sama5d2_xplained.h b/include/configs/sama5d2_xplained.h
index 435956d..7fb2bdc 100644
--- a/include/configs/sama5d2_xplained.h
+++ b/include/configs/sama5d2_xplained.h
@@ -15,6 +15,8 @@
 
 #include "at91-sama5_common.h"
 
+#define CONFIG_MISC_INIT_R
+
 /* SDRAM */
 #define CONFIG_NR_DRAM_BANKS		1
 #define CONFIG_SYS_SDRAM_BASE           ATMEL_BASE_DDRCS
@@ -54,6 +56,10 @@
 #define CONFIG_DOS_PARTITION
 #endif
 
+/* I2C */
+#define AT24MAC_ADDR		0x5c
+#define AT24MAC_REG		0x9a
+
 /* Ethernet Hardware */
 #define CONFIG_MACB
 #define CONFIG_RMII