arm64: dts: rockchip: drop #address-cells, #size-cells from rk3328 grf node

The device tree compiler gives the following warning:

    /syscon@ff100000: unnecessary #address-cells/#size-cells without
    "ranges" or child "reg" property

Since none of the grf node's direct child nodes have any reg properties,
remove the two properties from the grf node to silence the warning.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20200327030414.5903-5-wens@kernel.orgSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3328.dtsi

@@ -299,8 +299,6 @@ &pdmm0_sdi2_sleep
 	grf: syscon@ff100000 {
 		compatible = "rockchip,rk3328-grf", "syscon", "simple-mfd";
 		reg = <0x0 0xff100000 0x0 0x1000>;
-		#address-cells = <1>;
-		#size-cells = <1>;
 
 		io_domains: io-domains {
 			compatible = "rockchip,rk3328-io-voltage-domain";