[DEBUG] arm64: dts: rockchip: rock5bp: enable vsync debug gpio

Enable vsync GPIOs for the second camera/display.
On a Rock 5B+ this means:

Pin  1 = 3.3V
Pin  3 = ISP0 frame start
Pin  5 = ISP0 frame end
Pin  7 = VP0 vsync
Pin  9 = GND
Pin 11 = ISP1 frame start
Pin 13 = ISP1 frame end
Pin 15 = VP1 vsync

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>