ARM: dts: rockchip: add rk3288 watchdog clock

Add the clock property for the watchdog on rk3288 socs.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>

arch/arm/boot/dts/rk3288.dtsi

@@ -560,6 +560,7 @@ grf: syscon@ff770000 {
 	wdt: watchdog@ff800000 {
 		compatible = "rockchip,rk3288-wdt", "snps,dw-wdt";
 		reg = <0xff800000 0x100>;
+		clocks = <&cru PCLK_WDT>;
 		interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
 		status = "disabled";
 	};