ARM: dts: BCM5301X: Switch Luxul XWC-1000 to the new fixed partitions syntax

This new syntax is slightly better designed & uses "compatible" string.
For details see Documentation/devicetree/bindings/mtd/partition.txt .
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm/boot/dts/bcm4708-luxul-xwc-1000.dts

@@ -26,9 +26,15 @@ memory {
 
 	nand: nand@18028000 {
 		nandcs@0 {
-			partition@0 {
-				label = "ubi";
-				reg = <0x00000000 0x08000000>;
+			partitions {
+				compatible = "fixed-partitions";
+				#address-cells = <1>;
+				#size-cells = <1>;
+
+				partition@0 {
+					label = "ubi";
+					reg = <0x00000000 0x08000000>;
+				};
 			};
 		};
 	};