ARM: dts: rockchip: fix vop iommu-cells on rk322x

iommu-cells obviously needs to start with a "#".
Signed-off-by: Justin Swartz <justin.swartz@risingedge.co.za>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk322x.dtsi

@@ -579,7 +579,7 @@ vop_mmu: iommu@20053f00 {
 		interrupt-names = "vop_mmu";
 		clocks = <&cru ACLK_VOP>, <&cru HCLK_VOP>;
 		clock-names = "aclk", "iface";
-		iommu-cells = <0>;
+		#iommu-cells = <0>;
 		status = "disabled";
 	};