ARM: dts: socfpga: align NAND controller name with bindings

Bindings expect NAND controller node name to match certain patterns:

  socfpga_arria10_socdk_nand.dtb: nand@ffb90000: $nodename:0: 'nand@ffb90000' does not match '^nand-controller(@.*)?'
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>

arch/arm/boot/dts/intel/socfpga/socfpga.dtsi

@@ -768,7 +768,7 @@ mmc: mmc@ff704000 {
 			status = "disabled";
 		};
 
-		nand0: nand@ff900000 {
+		nand0: nand-controller@ff900000 {
 			#address-cells = <0x1>;
 			#size-cells = <0x0>;
 			compatible = "altr,socfpga-denali-nand";

arch/arm/boot/dts/intel/socfpga/socfpga_arria10.dtsi

@@ -669,7 +669,7 @@ mmc: mmc@ff808000 {
 			status = "disabled";
 		};
 
-		nand: nand@ffb90000 {
+		nand: nand-controller@ffb90000 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			compatible = "altr,socfpga-denali-nand";