ARM: dts: imx6ulz-bsh-smm-m2: Add BSH SMM-M2 IMX6ULZ SystemMaster

Add DTS of BSH SMM-M2 SystemMaster.

This version comes with:
- 128 MiB DDR3 RAM
- 256 MiB Nand
- wifi
- bluetooth

Signed-off-by: Ariel D'Alessandro <ariel.dalessandro@collabora.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>