ARM: at91: dt: usb-a9263: update shutdown controller

enable rtt and wakeup button (5 msec low)
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/usb_a9263.dts

@@ -47,6 +47,10 @@
 				status = "okay";
 			};
 
+			shdwc@fffffd10 {
+				atmel,wakeup-counter = <10>;
+				atmel,wakeup-rtt-timer;
+			};
 		};
 
 		nand0: nand@40000000 {