ARM: dts: sun7i: Enable USB DRC on cubieboard2

Enable the otg/drc usb controller on the cubieboard2.

Note this board has the otg-vbus connected directly to the 5v-dcc of
the board, so there is no vbus0 regulator, nor vbus0-det.

Signed-off-by: Ralph Benadski <benadski@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>