powerpc/5200: dts: digsy_mtc.dts: add timer0 and timer1 gpio properties

timer0 and timer1 pins are used as simple GPIO on this board.
Add gpio-controller and #gpio-cells properties to timer nodes
so that we can control gpio lines using available MPC52xx
GPT driver.
Signed-off-by: Anatolij Gustschin <agust@denx.de>

arch/powerpc/boot/dts/digsy_mtc.dts

@@ -23,7 +23,14 @@ memory {
 
 	soc5200@f0000000 {
 		timer@600 {	// General Purpose Timer
+			#gpio-cells = <2>;
 			fsl,has-wdt;
+			gpio-controller;
+		};
+
+		timer@610 {
+			#gpio-cells = <2>;
+			gpio-controller;
 		};
 
 		rtc@800 {