ARM: sun7i: fix PLL4 clock and add PLL8

Allwinner reworked the PLL4 clock in sun7i; so we need to change the
compatible. Additionally, PLL8 is compatible with this new PLL4
implementation, so let's add a node for it as well.
Signed-off-by: Emilio López <emilio@elopez.com.ar>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun7i-a20.dtsi

@@ -87,7 +87,7 @@ pll1: clk@01c20000 {
 
 		pll4: clk@01c20018 {
 			#clock-cells = <0>;
-			compatible = "allwinner,sun4i-a10-pll1-clk";
+			compatible = "allwinner,sun7i-a20-pll4-clk";
 			reg = <0x01c20018 0x4>;
 			clocks = <&osc24M>;
 			clock-output-names = "pll4";
@@ -109,6 +109,14 @@ pll6: clk@01c20028 {
 			clock-output-names = "pll6_sata", "pll6_other", "pll6";
 		};
 
+		pll8: clk@01c20040 {
+			#clock-cells = <0>;
+			compatible = "allwinner,sun7i-a20-pll4-clk";
+			reg = <0x01c20040 0x4>;
+			clocks = <&osc24M>;
+			clock-output-names = "pll8";
+		};
+
 		cpu: cpu@01c20054 {
 			#clock-cells = <0>;
 			compatible = "allwinner,sun4i-a10-cpu-clk";