arm64: dts: rockchip: enable DC charger detection pullup on Pinebook Pro

arm64: dts: rockchip: enable DC charger detection pullup on Pinebook Pro

On the Pinebook Pro the DC charger is detected via an open collector
transistor attached to a GPIO. This GPIO requires its pullup to be
enabled for the detection to work reliably.

Fixes: 71afb86830a5 ("arm64: dts: rockchip: Add initial support for Pinebook Pro")
Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Link: https://lore.kernel.org/r/20200414163952.1093784-3-t.schramm@manjaro.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>