ARM64: dts: meson-gx: Add shared CMA dma memory pool

The HDMI modes needs more CMA memory to be reserved at boot-time.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>

arch/arm64/boot/dts/amlogic/meson-gx.dtsi

@@ -71,6 +71,14 @@ secmon_reserved: secmon@10000000 {
 			reg = <0x0 0x10000000 0x0 0x200000>;
 			no-map;
 		};
+
+		linux,cma {
+			compatible = "shared-dma-pool";
+			reusable;
+			size = <0x0 0xbc00000>;
+			alignment = <0x0 0x400000>;
+			linux,cma-default;
+		};
 	};
 
 	cpus {