ls102xa: dcu: Add platform support for DCU on LS1021ATWR board

This patch adds the TWR_LCD_RGB card/HDMI options and the common
configuration for DCU on LS1021ATWR board.

Signed-off-by: Alison Wang <alison.wang@freescale.com>
diff --git a/board/freescale/ls1021atwr/Makefile b/board/freescale/ls1021atwr/Makefile
index b5df668..01296c0 100644
--- a/board/freescale/ls1021atwr/Makefile
+++ b/board/freescale/ls1021atwr/Makefile
@@ -5,3 +5,4 @@
 #
 
 obj-y += ls1021atwr.o
+obj-$(CONFIG_FSL_DCU_FB) += dcu.o