add shtc3 to i2c-sensors

This patch adds the shtc3 device tree parameters to the i2c-sensors
overlay.  The shtc3 driver needs no other configuration parameters, as the
i2c address is permanently baked in to the silicon.

Author: jsarrett

arch/arm/boot/dts/overlays/README

@@ -2605,6 +2605,9 @@ Params: addr                    Set the address for the ADT7410, AS73211,
                                 humidity sensors. Valid addresses 0x44-0x45,
                                 default 0x44
 
+        shtc3                   Select the Sensirion SHTC3 temperature and
+                                humidity sensors.
+
         si7020                  Select the Silicon Labs Si7013/20/21 humidity/
                                 temperature sensor
 

arch/arm/boot/dts/overlays/i2c-sensor-common.dtsi

@@ -548,6 +548,21 @@
 	};
 
 	fragment@36 {
+		target = <&i2cbus>;
+		__dormant__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "okay";
+
+			shtc3: shtc3@70 {
+				compatible = "sensirion,shtc3";
+				reg = <0x70>;
+				status = "okay";
+			};
+		};
+	};
+
+	fragment@37 {
 		target = <&i2cbus>;
 		__dormant__ {
 			#address-cells = <1>;
@@ -565,7 +580,7 @@
 		};
 	};
 
-	fragment@37 {
+	fragment@38 {
 		target = <&i2cbus>;
 		__dormant__ {
 			#address-cells = <1>;
@@ -579,7 +594,7 @@
 		};
 	};
 
-	fragment@38 {
+	fragment@39 {
 		target = <&i2cbus>;
 		__dormant__ {
 			#address-cells = <1>;
@@ -597,7 +612,7 @@
 		};
 	};
 
-	fragment@39 {
+	fragment@40 {
 		target = <&i2cbus>;
 		__dormant__ {
 			#address-cells = <1>;
@@ -615,7 +630,7 @@
 		};
 	};
 
-	fragment@40 {
+	fragment@41 {
 		target = <&i2cbus>;
 		__dormant__ {
 			#address-cells = <1>;
@@ -681,11 +696,12 @@
 		sht4x = <0>,"+32";
 		adt7410 = <0>,"+34";
 		ina238 = <0>,"+35";
-		hts221 = <0>,"+36+99";
-		veml6075 = <0>,"+37";
-		hdc3020 = <0>,"+38+99";
-		as73211 = <0>,"+39+99";
-		as7331 = <0>,"+40+99";
+		shtc3 = <0>,"+36";
+		hts221 = <0>,"+37+99";
+		veml6075 = <0>,"+38";
+		hdc3020 = <0>,"+39+99";
+		as73211 = <0>,"+40+99";
+		as7331 = <0>,"+41+99";
 
 		addr =	<&bme280>,"reg:0", <&bmp280>,"reg:0", <&tmp102>,"reg:0",
 			<&lm75>,"reg:0", <&hdc100x>,"reg:0", <&sht3x>,"reg:0",