ARM: dts: Cygnus: Add Broadcom iproc-static-adc DT node

This patch adds the DT node for Broadcom's iproc-static-adc
controller driver.
Signed-off-by: Raveendra Padasalagi <raveendra.padasalagi@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

arch/arm/boot/dts/bcm-cygnus.dtsi

@@ -366,5 +366,16 @@ touchscreen: touchscreen@180a6000 {
 			interrupts = <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>;
 			status = "disabled";
 		};
+
+		adc: adc@180a6000 {
+			compatible = "brcm,iproc-static-adc";
+			#io-channel-cells = <1>;
+			io-channel-ranges;
+			adc-syscon = <&ts_adc_syscon>;
+			clocks = <&asiu_clks BCM_CYGNUS_ASIU_ADC_CLK>;
+			clock-names = "tsc_clk";
+			interrupts = <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>;
+			status = "disabled";
+		};
 	};
 };