This patch adds the devicetree documentation required for Rockchip USB 3.0 core wrapper consisting of USB 3.0 controller IP from Synopsys and USB 3.0 PHY IP from Innosilicon. It supports DRD mode, and could operate in device mode (SS, HS, FS) and host mode (SS, HS, FS, LS). Change-Id: Ia240627c31cd3ff2f2d7f1a1faa9c7d88207d04f Signed-off-by: William Wu <wulf@rock-chips.com>