sunxi: Add support for Bananapi M2 Ultra

The Bananapi M2 Ultra is the first publicly available development board
featuring the R40 SoC.

This patch add barebone dtsi/dts files for the R40 and Bananapi M2 Ultra,
as well as a defconfig for it.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/board/sunxi/MAINTAINERS b/board/sunxi/MAINTAINERS
index 2a712fe..7ce2a32 100644
--- a/board/sunxi/MAINTAINERS
+++ b/board/sunxi/MAINTAINERS
@@ -109,6 +109,12 @@
 S:	Maintained
 F:	configs/Ampe_A76_defconfig
 
+BANANAPI M2 ULTRA BOARD
+M:	Chen-Yu Tsai <wens@csie.org>
+S:	Maintained
+F:	configs/Bananapi_M2_Ultra_defconfig
+F:	arch/arm/dts/sun8i-r40-bananapi-m2-ultra.dts
+
 COLOMBUS BOARD
 M:	Maxime Ripard <maxime.ripard@free-electrons.com>
 S:	Maintained