ARM: at91/dt: add GPBR nodes

Add GPBR (General Purpose Block Backup Registers) nodes.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
diff --git a/arch/arm/boot/dts/at91sam9261.dtsi b/arch/arm/boot/dts/at91sam9261.dtsi
index 06b11fc..cdb9ed6 100644
--- a/arch/arm/boot/dts/at91sam9261.dtsi
+++ b/arch/arm/boot/dts/at91sam9261.dtsi
@@ -842,6 +842,12 @@
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				status = "disabled";
 			};
+
+			gpbr: syscon@fffffd50 {
+				compatible = "atmel,at91sam9260-gpbr", "syscon";
+				reg = <0xfffffd50 0x10>;
+				status = "disabled";
+			};
 		};
 	};