dt-bindings: gpu: mali-utgard: Add compatible for A64 Mali

Allwinner A64 has Mali-400MP2, so document the relevant compatible
as "allwinner,sun50i-a64-mali" along with reset line.
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

Documentation/devicetree/bindings/gpu/arm,mali-utgard.txt

@@ -11,6 +11,7 @@ Required properties:
       + allwinner,sun4i-a10-mali
       + allwinner,sun7i-a20-mali
       + allwinner,sun8i-h3-mali
+      + allwinner,sun50i-a64-mali
       + allwinner,sun50i-h5-mali
       + amlogic,meson-gxbb-mali
       + amlogic,meson-gxl-mali
@@ -73,6 +74,10 @@ to specify one more vendor-specific compatible, among:
     Required properties:
       * resets: phandle to the reset line for the GPU
 
+  - allwinner,sun50i-a64-mali
+    Required properties:
+      * resets: phandle to the reset line for the GPU
+
   - allwinner,sun50i-h5-mali
     Required properties:
       * resets: phandle to the reset line for the GPU