rockchip: board: lion-rk3368: add support for the RK3368-uQ7

rockchip: board: lion-rk3368: add support for the RK3368-uQ7

The RK3368-uQ7 (codenamed 'Lion') is a micro-Qseven (40mm x 70mm,
MXM-230 edge connector compatible with the Qseven specification)
form-factor system-on-module based on the octo-core Rockchip RK3368.
It is designed, supported and manufactured by Theobroma Systems.

It provides the following features:
 - 8x Cortex-A53 (in 2 clusters of 4 cores each)
 - (on-module) up to 4GB of DDR3 memory
 - (on-module) SPI-NOR flash
 - (on-module) eMMC
 - Gigabit Ethernet (with an on-module KSZ9031 PHY)
 - USB
 - HDMI
 - MIPI-DSI/single-channel LVDS (muxed on the 'LVDS-A' pin-group)
 - various 'slow' interfaces (e.g. UART, SPI, I2C, I2S, ...)

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>