arm: ls102xa: Add basic support for LS1021ATWR board

LS102xA is an ARMv7 implementation. This patch is to add
basic support for LS1021ATWR board.
 One DDR controller
 DUART1 is used as the console

For the detail board information, please refer to README.

Signed-off-by: Chen Lu <chen.lu@freescale.com>
Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Alison Wang <alison.wang@freescale.com>
diff --git a/configs/ls1021atwr_nor_defconfig b/configs/ls1021atwr_nor_defconfig
new file mode 100644
index 0000000..5f465d3
--- /dev/null
+++ b/configs/ls1021atwr_nor_defconfig
@@ -0,0 +1,2 @@
+CONFIG_ARM=y
+CONFIG_TARGET_LS1021ATWR=y