board: sama5d2_xplained: Replace code to set mac address

Replace the code to set the ethernet mac address with the code from
the common folder.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/sama5d2_xplained_spiflash_defconfig b/configs/sama5d2_xplained_spiflash_defconfig
index c64b8b8..2ecedd9 100644
--- a/configs/sama5d2_xplained_spiflash_defconfig
+++ b/configs/sama5d2_xplained_spiflash_defconfig
@@ -49,6 +49,7 @@
 CONFIG_ATMEL_PIO4=y
 CONFIG_DM_I2C=y
 CONFIG_SYS_I2C_AT91=y
+CONFIG_I2C_EEPROM=y
 CONFIG_DM_MMC=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_ATMEL=y