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/configs/Bananapi_M2_Ultra_defconfig b/configs/Bananapi_M2_Ultra_defconfig
new file mode 100644
index 0000000..c6da727
--- /dev/null
+++ b/configs/Bananapi_M2_Ultra_defconfig
@@ -0,0 +1,15 @@
+CONFIG_ARM=y
+CONFIG_ARCH_SUNXI=y
+CONFIG_MACH_SUN8I_R40=y
+CONFIG_DRAM_CLK=576
+CONFIG_DRAM_ZQ=3881979
+CONFIG_DRAM_ODT_EN=y
+CONFIG_MMC0_CD_PIN="PH13"
+CONFIG_MMC_SUNXI_SLOT_EXTRA=2
+CONFIG_DEFAULT_DEVICE_TREE="sun8i-r40-bananapi-m2-ultra"
+# CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
+CONFIG_SPL=y
+CONFIG_SPL_I2C_SUPPORT=y
+# CONFIG_CMD_IMLS is not set
+# CONFIG_CMD_FLASH is not set
+# CONFIG_CMD_FPGA is not set