dts: hisi: fixes no syscon fault when init mdio

When linux start up, we get the log below:
"Hi-HNS_MDIO 803c0000.mdio: no syscon hisilicon,peri-c-subctrl
mdio_bus mdio@803c0000: mdio sys ctl reg has not maped"

The source code about the subctrl is dealt syscon, but dts doesn't.
It cause such fault, so this patch adds the syscon info on dts files to
fixes it.
Signed-off-by: Kejian Yan <yankejian@huawei.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/arm/hisilicon/hisilicon.txt

@@ -187,6 +187,22 @@ Example:
 		reg = <0xb0000000 0x10000>;
 	};
 
+Hisilicon HiP05 PERISUB system controller
+
+Required properties:
+- compatible : "hisilicon,hip05-perisubc", "syscon";
+- reg : Register address and size
+
+The HiP05 PERISUB system controller is shared by peripheral controllers in
+HiP05 Soc to implement some basic configurations. The peripheral
+controllers include mdio, ddr, iic, uart, timer and so on.
+
+Example:
+	/* for HiP05 perisub-ctrl-c system */
+	peri_c_subctrl: syscon@80000000 {
+		compatible = "hisilicon,hip05-perisubc", "syscon";
+		reg = <0x0 0x80000000 0x0 0x10000>;
+	};
 -----------------------------------------------------------------------
 Hisilicon CPU controller
 

arch/arm64/boot/dts/hisilicon/hip05.dtsi

@@ -246,6 +246,11 @@ refclk200mhz: refclk200mhz {
 			clock-frequency = <200000000>;
 		};
 
+		peri_c_subctrl: syscon@80000000 {
+			compatible = "hisilicon,hip05-perisubc", "syscon";
+			reg = < 0x0 0x80000000 0x0 0x10000>;
+		};
+
 		uart0: uart@80300000 {
 			compatible = "snps,dw-apb-uart";
 			reg = <0x0 0x80300000 0x0 0x10000>;

arch/arm64/boot/dts/hisilicon/hip05_hns.dtsi

@@ -10,8 +10,8 @@ soc0_mdio0: mdio@803c0000 {
 		#address-cells = <1>;
 		#size-cells = <0>;
 		compatible = "hisilicon,hns-mdio";
-		reg = <0x0 0x803c0000 0x0 0x10000
-		       0x0 0x80000000 0x0 0x10000>;
+		reg = <0x0 0x803c0000 0x0 0x10000>;
+		subctrl-vbase = <&peri_c_subctrl>;
 
 		soc0_phy0: ethernet-phy@0 {
 			reg = <0x0>;