ARC: [plat-axs103] use clk driver #2: Add core pll node to DT to manage cpu clk

Add core pll node (core_clk) to manage cpu frequency.
core_clk represents pll itself.
input_clk represents clock signal source (basically xtal) which
comes to pll input.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/boot/dts/axc003.dtsi

@@ -24,10 +24,17 @@
 
 		ranges = <0x00000000 0x0 0xf0000000 0x10000000>;
 
-		core_clk: core_clk {
+		input_clk: input-clk {
 			#clock-cells = <0>;
 			compatible = "fixed-clock";
-			clock-frequency = <90000000>;
+			clock-frequency = <33333333>;
+		};
+
+		core_clk: core-clk@80 {
+			compatible = "snps,axs10x-arc-pll-clock";
+			reg = <0x80 0x10>, <0x100 0x10>;
+			#clock-cells = <0>;
+			clocks = <&input_clk>;
 		};
 
 		core_intc: archs-intc@cpu {

arch/arc/boot/dts/axc003_idu.dtsi

@@ -24,10 +24,17 @@
 
 		ranges = <0x00000000 0x0 0xf0000000 0x10000000>;
 
-		core_clk: core_clk {
+		input_clk: input-clk {
 			#clock-cells = <0>;
 			compatible = "fixed-clock";
-			clock-frequency = <100000000>;
+			clock-frequency = <33333333>;
+		};
+
+		core_clk: core-clk@80 {
+			compatible = "snps,axs10x-arc-pll-clock";
+			reg = <0x80 0x10>, <0x100 0x10>;
+			#clock-cells = <0>;
+			clocks = <&input_clk>;
 		};
 
 		core_intc: archs-intc@cpu {