nds32: Support AE3XX platform.

Support Andestech AE3xx platform: serial, timer device tree flow.

Signed-off-by: rick <rick@andestech.com>
diff --git a/configs/adp-ae3xx_defconfig b/configs/adp-ae3xx_defconfig
new file mode 100644
index 0000000..95df275
--- /dev/null
+++ b/configs/adp-ae3xx_defconfig
@@ -0,0 +1,25 @@
+CONFIG_NDS32=y
+CONFIG_TARGET_ADP_AE3XX=y
+CONFIG_DEFAULT_DEVICE_TREE="ae3xx"
+CONFIG_FIT=y
+CONFIG_BOOTDELAY=3
+CONFIG_SYS_PROMPT="NDS32 # "
+CONFIG_CMD_MMC=y
+# CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_PING=y
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_DATE=y
+CONFIG_CMD_EXT2=y
+CONFIG_CMD_FAT=y
+CONFIG_MMC=y
+CONFIG_MTD_NOR_FLASH=y
+CONFIG_BAUDRATE=38400
+CONFIG_OF_CONTROL=y
+CONFIG_DM=y
+CONFIG_MTD=y
+CONFIG_CFI_FLASH=y
+CONFIG_DM_SERIAL=y
+CONFIG_SYS_NS16550=y
+CONFIG_TIMER=y
+CONFIG_AE3XX_TIMER=y