arm64: dts: rockchip: set rockpro64 usbc dr_mode as host

The usb-c port on the rockpro64 does not detect devices reliably when in otg mode.
Setting the mode to "host" allows the port to work reliably.
This aligns with the pinebook-pro configuration.

Signed-off-by: Peter Geis <pgwipeout@gmail.com>
Link: https://lore.kernel.org/r/20200614142950.1120694-1-pgwipeout@gmail.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>