arm64: dts: rockchip: Fix Pinebook Pro FUSB302 interrupt

Although the FUSB302 driver has apparently supported the "fcs,int_n"
property since the beginning, the DT binding has never documented it,
and in fact defines a standard "interrupts" property as required. It's
also questionable whether the GPIO specifier with GPIO_ACTIVE_HIGH is
even correct, since the FUSB302 datasheet says INT_N is an "Active-LOW
open-drain interrupt output", and the Pinebook Pro schematic shows it
wired directly to the GPIO pin.

Just use the standard property like all the other RK3399 boards sharing
the same design.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/f731122c5ccde4e3d6d149a9d7bf01708b4279f7.1587736459.git.robin.murphy@arm.com


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