sunxi: add support for Banana Pi M2 Berry

sunxi: add support for Banana Pi M2 Berry

CPU: Allwinner V40 quad-core Cortex A7 @ 1.2GHz
Memory: 1GB DDR3
Storage: SDcard, native SATA
Network: 10/100/1000M ethernet, Ampak AP6212 wifi + BT
USB: 4x USB 2.0

Installation:
Use the standard sunxi installation to an SD-card.

While the board is very similar to the M2 Ultra board
(the V40 is the automotive version of the R40), as both
the u-boot and kernel supports them separately, and some
pins are different, let's add a separate device spec.

Signed-off-by: Zoltan HERPAI <wigyori@uid0.hu>