sunxi: Add defconfig and dts file for inet86dz board

The inet86dz board is a board used in 7" tablets from various oems.

These tablets are a23 based 7" tablets featuring a 1024x600 LCD,
512MB RAM, 4G NAND, rtl8188etv usb wifi, gsl1680 touchschreen,
micro-sd slot, 3.5mm headphone jack and a micro-usb otg connector
which doubles as charging port.

The dts file this commit adds is identical to the one submitted to
the upstream kernel.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/board/sunxi/MAINTAINERS b/board/sunxi/MAINTAINERS
index 4f8d950..de5207e 100644
--- a/board/sunxi/MAINTAINERS
+++ b/board/sunxi/MAINTAINERS
@@ -54,6 +54,7 @@
 F:	include/configs/sun8i.h
 F:	configs/ga10h_v1_1_defconfig
 F:	configs/gt90h_v4_defconfig
+F:	configs/inet86dz_defconfig
 F:	configs/orangepi_2_defconfig
 F:	configs/orangepi_one_defconfig
 F:	configs/orangepi_pc_defconfig