dtoverlays: Add sync configuration option to imx296 overlay

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

Author: 6by9

arch/arm/boot/dts/overlays/README

@@ -2816,6 +2816,7 @@ Params: rotation                Mounting rotation of the camera sensor (0 or
                                 (the default), 37125000 or 74250000.
         always-on               Leave the regulator powered up, to stop the
                                 camera clamping I/Os such as XTRIG to 0V.
+        sync-sink               Configure as synchronisation sink.
 
 
 Name:   imx327

arch/arm/boot/dts/overlays/imx296-overlay.dts

@@ -116,5 +116,6 @@
 		       <&imx296>, "avdd-supply:0=",<&cam0_reg>;
 		clock-frequency = <&clk_over>, "clock-frequency:0";
 		always-on = <0>, "+99";
+		sync-sink = <&imx296>,"trigger-mode:0";
 	};
 };