dt-bindings: arm: amlogic: Add Meson G12A binding

Introduce new bindings for the Meson G12A SoC

Signed-off-by: Jianxin Pan <jianxin.pan@amlogic.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

Documentation/devicetree/bindings/arm/amlogic.txt

@@ -57,6 +57,10 @@ Boards with the Amlogic Meson AXG A113D SoC shall have the following properties:
   Required root node property:
     compatible: "amlogic,a113d", "amlogic,meson-axg";
 
+Boards with the Amlogic Meson G12A S905D2 SoC shall have the following properties:
+  Required root node property:
+    compatible: "amlogic,g12a";
+
 Board compatible values (alphabetically, grouped by SoC):
 
   - "geniatech,atv1200" (Meson6)
@@ -101,6 +105,8 @@ Board compatible values (alphabetically, grouped by SoC):
 
   - "amlogic,s400" (Meson axg a113d)
 
+  - "amlogic,u200" (Meson g12a s905d2)
+
 Amlogic Meson Firmware registers Interface
 ------------------------------------------