ARM: dts: Enable USB host0 (EHCI) on rk3288-evb

This is the top USB port on the evb (the one closest to the Ethernet
connector).

Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>