ls2080a/dts: Add little endian property for GPIO IP block

The GPIO block for ls2080a platform has little endian registers,
the GPIO driver needs this property to read/write registers by
right interface.
Signed-off-by: Liu Gang <Gang.Liu@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

arch/arm64/boot/dts/freescale/fsl-ls2080a.dtsi

@@ -278,6 +278,7 @@ gpio0: gpio@2300000 {
 			reg = <0x0 0x2300000 0x0 0x10000>;
 			interrupts = <0 36 0x4>; /* Level high type */
 			gpio-controller;
+			little-endian;
 			#gpio-cells = <2>;
 			interrupt-controller;
 			#interrupt-cells = <2>;
@@ -288,6 +289,7 @@ gpio1: gpio@2310000 {
 			reg = <0x0 0x2310000 0x0 0x10000>;
 			interrupts = <0 36 0x4>; /* Level high type */
 			gpio-controller;
+			little-endian;
 			#gpio-cells = <2>;
 			interrupt-controller;
 			#interrupt-cells = <2>;
@@ -298,6 +300,7 @@ gpio2: gpio@2320000 {
 			reg = <0x0 0x2320000 0x0 0x10000>;
 			interrupts = <0 37 0x4>; /* Level high type */
 			gpio-controller;
+			little-endian;
 			#gpio-cells = <2>;
 			interrupt-controller;
 			#interrupt-cells = <2>;
@@ -308,6 +311,7 @@ gpio3: gpio@2330000 {
 			reg = <0x0 0x2330000 0x0 0x10000>;
 			interrupts = <0 37 0x4>; /* Level high type */
 			gpio-controller;
+			little-endian;
 			#gpio-cells = <2>;
 			interrupt-controller;
 			#interrupt-cells = <2>;