arm64: dts: lx2160a: Update can node property

fsl,clk-source property is of type uint8 and need to be defined as
"/bits/ 8 <0>". Simply setting value to 0 raise warning:
can@2180000: fsl,clk-source:0: [0, 0, 0, 0] is too long
Signed-off-by: Kuldeep Singh <singh.kuldeep87k@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/fsl-lx2160a.dtsi

@@ -909,7 +909,7 @@ can0: can@2180000 {
 					    QORIQ_CLK_PLL_DIV(8)>,
 				 <&clockgen QORIQ_CLK_SYSCLK 0>;
 			clock-names = "ipg", "per";
-			fsl,clk-source = <0>;
+			fsl,clk-source = /bits/ 8 <0>;
 			status = "disabled";
 		};
 
@@ -921,7 +921,7 @@ can1: can@2190000 {
 					    QORIQ_CLK_PLL_DIV(8)>,
 				 <&clockgen QORIQ_CLK_SYSCLK 0>;
 			clock-names = "ipg", "per";
-			fsl,clk-source = <0>;
+			fsl,clk-source = /bits/ 8 <0>;
 			status = "disabled";
 		};