arm: imx6q: Add devicetree support for Engicam i.CoreM6 Quad/Dual

arm: imx6q: Add devicetree support for Engicam i.CoreM6 Quad/Dual

i.CoreM6 Quad/Dual modules are system on module solutions
manufactured by Engicam with following characteristics:
CPU           NXP i.MX6 DQ, 800MHz
RAM           1GB, 32, 64 bit, DDR3-800/1066
NAND          SLC,512MB
Power supply  Single 5V
MAX LCD RES   FULLHD

and more info at
http://www.engicam.com/en/products/embedded/som/sodimm/i-core-m6s-dl-d-q

Cc: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Matteo Lisi <matteo.lisi@engicam.com>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>