Documentation: DT: Add entry for FSL LS1012A RDB, FRDM, QDS boards

Signed-off-by: Harninder Rai <harninder.rai@nxp.com>
Signed-off-by: Bhaskar Upadhaya <Bhaskar.Upadhaya@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

Documentation/devicetree/bindings/arm/fsl.txt

@@ -139,6 +139,22 @@ Example:
 Freescale ARMv8 based Layerscape SoC family Device Tree Bindings
 ----------------------------------------------------------------
 
+LS1012A SoC
+Required root node properties:
+    - compatible = "fsl,ls1012a";
+
+LS1012A ARMv8 based RDB Board
+Required root node properties:
+    - compatible = "fsl,ls1012a-rdb", "fsl,ls1012a";
+
+LS1012A ARMv8 based FRDM Board
+Required root node properties:
+    - compatible = "fsl,ls1012a-frdm", "fsl,ls1012a";
+
+LS1012A ARMv8 based QDS Board
+Required root node properties:
+    - compatible = "fsl,ls1012a-qds", "fsl,ls1012a";
+
 LS1043A SoC
 Required root node properties:
     - compatible = "fsl,ls1043a";