sunxi: Add initial support for R40

The R40 is the successor to the A20. It is a hybrid of the A20, A33
and the H3.

The R40's PIO controller is compatible with the A20,
Reuse the A20 UART and I2C muxing code by adding the R40's macro.

The display pipeline is the newer DE 2.0 variant.
Block enabling video on R40 for now.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
index 6735558..3df7077 100644
--- a/board/sunxi/Kconfig
+++ b/board/sunxi/Kconfig
@@ -134,6 +134,11 @@
 	select MACH_SUNXI_H3_H5
 	select ARMV7_BOOT_SEC_DEFAULT if OLD_SUNXI_KERNEL_COMPAT
 
+config MACH_SUN8I_R40
+	bool "sun8i (Allwinner R40)"
+	select CPU_V7
+	select SUNXI_GEN_SUN6I
+
 config MACH_SUN9I
 	bool "sun9i (Allwinner A80)"
 	select CPU_V7
@@ -163,6 +168,7 @@
 	default y if MACH_SUN8I_A33
 	default y if MACH_SUN8I_A83T
 	default y if MACH_SUNXI_H3_H5
+	default y if MACH_SUN8I_R40
 
 config RESERVE_ALLWINNER_BOOT0_HEADER
 	bool "reserve space for Allwinner boot0 header"
@@ -528,6 +534,7 @@
 	bool "Enable graphical uboot console on HDMI, LCD or VGA"
 	depends on !MACH_SUN8I_A83T
 	depends on !MACH_SUNXI_H3_H5
+	depends on !MACH_SUN8I_R40
 	depends on !MACH_SUN9I
 	depends on !MACH_SUN50I
 	default y