ARM: dts: stm32: add adc support on stm32mp135f-dk

Configure ADC support on stm32mp135f-dk. ADC can be used for
USB Type-C CC1 & CC2 pins wired to in6 & in12.

Signed-off-by: Olivier Moysan <[e-mail]>
Signed-off-by: Alexandre Torgue <[e-mail]>

arch/arm/boot/dts/stm32mp135f-dk.dts

···
 	};
 };
 
+&adc_1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&adc1_usb_cc_pins_a>;
+	vdda-supply = <&vdd_adc>;
+	vref-supply = <&vdd_adc>;
+	status = "okay";
+	adc1: adc@0 {
+		status = "okay";
+		/*
+		 * Type-C USB_PWR_CC1 & USB_PWR_CC2 on in6 & in12.
+		 * Use at least 5 * RC time, e.g. 5 * (Rp + Rd) * C:
+		 * 5 * (5.1 + 47kOhms) * 5pF => 1.3us.
+		 * Use arbitrary margin here (e.g. 5us).
+		 */
+		channel@6 {
+			reg = <6>;
+			st,min-sample-time-ns = <5000>;
+		};
+		channel@12 {
+			reg = <12>;
+			st,min-sample-time-ns = <5000>;
+		};
+	};
+};
+
 &i2c1 {
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&i2c1_pins_a>;