ARM: at91: dt: usb-a9260: update shutdown controller

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

arch/arm/boot/dts/usb_a9260.dts

@@ -20,4 +20,13 @@ chosen {
 	memory {
 		reg = <0x20000000 0x4000000>;
 	};
+
+	ahb {
+		apb {
+			shdwc@fffffd10 {
+				atmel,wakeup-counter = <10>;
+				atmel,wakeup-rtt-timer;
+			};
+		};
+	};
 };