sunxi: add support for Cubietruck booting in FEL mode

Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Jens Kuske <jenskuske@gmail.com>
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Reviewed-by: Tom Rini <trini@ti.com>
Reviewed-by: Marek Vasut <marex@denx.de>
diff --git a/board/sunxi/Makefile b/board/sunxi/Makefile
index 559112e..18b1e11 100644
--- a/board/sunxi/Makefile
+++ b/board/sunxi/Makefile
@@ -9,3 +9,4 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 obj-y	+= board.o
+obj-$(CONFIG_CUBIETRUCK)	+= dram_cubietruck.o