ARM: dts: sun6i: Add support for Yones Toptech bs1078v2 tablets

The bs1078v2 is a pcb found in 10.1" tablets with an A31 soc, 1G RAM
and 8G NAND, rtl8723as usb wifi, 1 micro USB OTG port, 1 USB HOST port

This commit adds a dts for v2 of the bs1078 pcb.

Signed-off-by: Lawrence Yu <lyu@micile.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>