x86: add Roqos Core RC10 ethernet interfaces

x86: add Roqos Core RC10 ethernet interfaces

eth0 -> single NIC (i211at)
eth1 -> single NIC (i211at) -> 4-port unmanaged switch (BCM53125U)

Notes
UART is exposed on J4 connector, pinout starting from pin marked 1:
1. GND, 2. NC?, 3. NC?, 4. RX, 5. TX, 6. NC?
baud: 115200, parity: none, flow control: none
The board is setup by coreboot with UEFI. To enter setup screen hold
ESC key on boot.
The 5-LED multicolor matrix is attached on first I2C device named
"Synopsys DesignWare I2C adapter" at address 0x60. Controlling values
are stored in /opt/roqos/etc/rcLED.conf of original firmware.
Remember to backup the original firmware, there are no downloadable
copies.

Signed-off-by: Tomasz Maciej Nowak <tmn505@gmail.com>