arm: atmel: Add SAMA5D2 Xplained board

The board supports following features:
 - Boot media support: SD card/e.MMC/SPI flash,
 - Support LCD display (optional, disabled by default),
 - Support ethernet,
 - Support USB mass storage.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
[fix checkpatch warnings]
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/configs/sama5d2_xplained_mmc_defconfig b/configs/sama5d2_xplained_mmc_defconfig
new file mode 100644
index 0000000..c1dcbef
--- /dev/null
+++ b/configs/sama5d2_xplained_mmc_defconfig
@@ -0,0 +1,11 @@
+CONFIG_ARM=y
+CONFIG_ARCH_AT91=y
+CONFIG_TARGET_SAMA5D2_XPLAINED=y
+CONFIG_SYS_EXTRA_OPTIONS="SAMA5D2,SYS_USE_MMC"
+# CONFIG_CMD_IMI is not set
+# CONFIG_CMD_IMLS is not set
+# CONFIG_CMD_LOADS is not set
+# CONFIG_CMD_FLASH is not set
+CONFIG_CMD_SF=y
+# CONFIG_CMD_FPGA is not set
+CONFIG_SPI_FLASH=y