ARM: dts: imx7d: cl-som-imx7: add basic module support

ARM: dts: imx7d: cl-som-imx7: add basic module support

CL-SOM-iMX7 is a miniature System-on-Module (SoM) based on
Freescale i.MX7 System-on-Chip family.

http://www.compulab.co.il/products/computer-on-modules/cl-som-imx7-freescale-i-mx-7-system-on-module/

Add basic DT support for standalone module (without a carrier board):

* Memory configuration
* eMMC
* 2x Gigabit Ethernet ports (FEC1 and FEC2)
* I2C2 bus
  * EEPROM
  * PCA9555 GPIO extender
  * PMIC
* UART1
* USB OTG port

Signed-off-by: Ilya Ledvich <ilya@compulab.co.il>
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>