dt-bindings: arm: Add bindings for SP9860G

Added bindings for Spreadtrum SP9860G board and SC9860 SoC.
This patch also revised bindings of SC9836 to make the format
more clear.
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/arm/sprd.txt

 Spreadtrum SoC Platforms Device Tree Bindings
 ----------------------------------------------------
 
-Sharkl64 is a Spreadtrum's SoC Platform which is based
-on ARM 64-bit processor.
+SC9836 openphone Board
+Required root node properties:
+	- compatible = "sprd,sc9836-openphone", "sprd,sc9836";
 
-SC9836 openphone board with SC9836 SoC based on the
-Sharkl64 Platform shall have the following properties.
+SC9860 SoC
+Required root node properties:
+	- compatible = "sprd,sc9860"
 
+SP9860G 3GFHD Board
 Required root node properties:
-        - compatible = "sprd,sc9836-openphone", "sprd,sc9836";
+	- compatible = "sprd,sp9860g-1h10", "sprd,sc9860";