sun8i: h2: Add initial Orange Pi R1 support

Orange Pi R1 is an open-source single-board computer using the
Allwinner H2+ SOC.

H2+ Orange Pi R1 has
 - Quad-core Cortex-A7
 - 256MB DDR3
 - micrSD slot
 - 128MBit SPI Nor flash
 - Debug TTL UART
 - 100MBit/s Ethernet (H2+)
 - 100MBit/s Ethernet (RTL8152B)
 - Wifi (RTL8189ETV)
 - USB 2.0 OTG + power supply
This board is very similar to the Orange Pi Zero.

The device tree file is copied from the Linux kernel 4.17.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
diff --git a/board/sunxi/MAINTAINERS b/board/sunxi/MAINTAINERS
index e90c87b..6ebf612 100644
--- a/board/sunxi/MAINTAINERS
+++ b/board/sunxi/MAINTAINERS
@@ -355,6 +355,11 @@
 S:	Maintained
 F:	configs/orangepi_prime_defconfig
 
+ORANGEPI R1 BOARD
+M:	Hauke Mehrtens <hauke@hauke-m.de>
+S:	Maintained
+F:	configs/orangepi_r1_defconfig
+
 PINE64 BOARDS
 M:	Andre Przywara <andre.przywara@arm.com>
 S:	Maintained