Merge nand stuff from Boris
FIXUP: for eb8ca6b ARM: sun4i: dt: Add pin muxing options for SPI

This is intended as a fixup for the following commit in sunxi-devel:
eb8ca6b ARM: sun4i: dt: Add pin muxing options for SPI

One pin group was declared wrong due to eye issues.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
ARM: sun4i: cubieboard: Add spidev node for SPI0

No device is connected to this SPI bus, and its pins are exposed to
the outside world. Enable spidev for this SPI bus.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
ARM: dt/sunxi: add NFC node to Allwinner A10 SoC

Add NAND Flash controller node definition to the A10 SoC.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
ARM: dt/sunxi: add NAND controller pin definitions

The pinout is identical to the one on A20 SoCs.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
ARM: sunxi/dt: enable NAND on cubieboard board

Only ONFI timing mode 0 is enabled for now, as it is unclear from the
NAND chip's datasheet whether it can operate reliably with tighter
timings.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>