arm: ls1021atwr: Split off board device tree

Move /chosen node out of the board device tree.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/ls1021atwr_nor_defconfig b/configs/ls1021atwr_nor_defconfig
index 2b79443..b7b3a8d 100644
--- a/configs/ls1021atwr_nor_defconfig
+++ b/configs/ls1021atwr_nor_defconfig
@@ -1,7 +1,7 @@
 CONFIG_ARM=y
 CONFIG_TARGET_LS1021ATWR=y
 CONFIG_DM_SERIAL=y
-CONFIG_DEFAULT_DEVICE_TREE="ls1021a-twr"
+CONFIG_DEFAULT_DEVICE_TREE="ls1021a-twr-duart"
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_OF_CONTROL=y
 CONFIG_DM=y