arm: mvebu: add .dts file for Synology DS414

Synology DS414 is a 4-bay NAS powered by a Marvell Armada XP
(mv78230 dual-core @1.33Ghz). It is very similar on many aspects
to previous 4-bay synology models based on Marvell kirkwood SoC.
Here is a short summary of the device:

 - 1GB RAM
 - Boot on SPI flash (64Mbit Micron N25Q064)
 - 2 GbE interfaces (Armada MAC connected to two Marvell 88E1512
   PHY via RGMII)
 - 1 front USB 2.0 ports (directly handled by the Armada 370)
 - 2 rear USB 3.0 ports (handled by an EtronTech EJ168A XHCI
   controller on the PCIe bus)
 - 4 internal SATA ports handled by a Marvell 88SX7042 SATA-II
   controller on the PCIe bus)
 - Seiko S-35390A I2C RTC chip
 - UART0 providing serial console
 - UART1 used for poweroff (connected to a Microchip PIC16F883)

Additional note: the front LEDs the and the two fans are not directly
connected to the SoC and under its control. The former are presumably
driven by the SATA controller, the latter by the PIC.

[ jac: fixed up s/ge[01]_rgmii_pins/pmx_ge[01]_rgmii/ to match
armada-xp.dtsi ]

Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Link: https://lkml.kernel.org/r/5b678d6d1f2f42f4bf0d087878b9d8024d463ea7.1416613429.git.arno@natisbad.org


Signed-off-by: Jason Cooper <jason@lakedaemon.net>