ARM: dts: ls1021a: fix board compatible to follow binding schema

Align the compatible strings with the board binding defined in schema
file.
Signed-off-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/ls1021a-tsn.dts

@@ -8,6 +8,7 @@
 
 / {
 	model = "NXP LS1021A-TSN Board";
+	compatible = "fsl,ls1021a-tsn", "fsl,ls1021a";
 
 	sys_mclk: clock-mclk {
 		compatible = "fixed-clock";

arch/arm/boot/dts/ls1021a.dtsi

@@ -9,7 +9,6 @@
 / {
 	#address-cells = <2>;
 	#size-cells = <2>;
-	compatible = "fsl,ls1021a";
 	interrupt-parent = <&gic>;
 
 	aliases {