arm: imx6ul: Add Engicam Is.IoT MX6UL Starter Kit initial support

Boot from MMC:
-------------
U-Boot SPL 2017.01-rc2-gba3c151-dirty (Jan 02 2017 - 16:59:33)
Trying to boot from MMC1

U-Boot 2017.01-rc2-gba3c151-dirty (Jan 02 2017 - 16:59:33 +0100)

CPU:   Freescale i.MX6UL rev1.1 528 MHz (running at 396 MHz)
CPU:   Industrial temperature grade (-40C to 105C) at 33C
Reset cause: POR
Model: Engicam Is.IoT MX6UL Starterkit
DRAM:  512 MiB
MMC:   FSL_SDHC: 0
*** Warning - bad CRC, using default environment

In:    serial
Out:   serial
Err:   serial
Net:   CPU Net Initialization Failed
No ethernet found.
Hit any key to stop autoboot:  0
isiotmx6ul>

Cc: Stefano Babic <sbabic@denx.de>
Cc: Matteo Lisi <matteo.lisi@engicam.com>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>