ramips: add support for the GnuBee Personal Cloud One

ramips: add support for the GnuBee Personal Cloud One

    The GnuBee Personal Cloud One crowdfunded on https://www.crowdsupply.com
    It is a low-cost, low-power, network-attached storage device.

    Specifications:

    - SoC: MediaTek MT7621AT
    - RAM: DDR3 512 MB
    - Flash: 32 MB
    - Six SATA ports for 2.5" Drives
    - One micro SDcard
    - One USB 3.0
    - Two USB 2.0
    - Gigabit Ethernet: 1 x WAN and 1 x LAN
    - UART 3.5mm Audio Jack or 3 pin header - 57600 8N1
    - Four GPIOs available on a pin header

    Flash instructions:

    The GnuBee Personal Cloud One ships with libreCMC installed.
    libreCMC is a Free Software Foundation approved fork of LEDE/OpenWrt.
    As such one can upgrade using the webinterface or sysupgrade.

    Das U-Boot has multiple options for recovery or updates including :

    - USB
    - http
    - tftp

Signed-off-by: L. D. Pinney <ldpinney@gmail.com>
[use switchdev led trigger, all interfaces are in vlan1; rename leds
according to board.d setting; remove ge2 group from the pinmux, this
group doesn't exist in the driver]
Signed-off-by: Mathias Kresin <dev@kresin.me>