dts: arm: stm32g0: add mcos node

The newly added mcos node contains two childreen `mco1` and `mco2` that can
be used to output different clocks on the MCO pins of the stm32g0
microcontrollers.

Signed-off-by: Andreas Schuster <[email protected]>

Author: schuam

dts/arm/st/g0/stm32g0.dtsi

@@ -94,6 +94,18 @@
 		};
 	};
 
+	mcos {
+		mco1: mco1 {
+			compatible = "st,stm32-clock-mco";
+			status = "disabled";
+		};
+
+		mco2: mco2 {
+			compatible = "st,stm32-clock-mco";
+			status = "disabled";
+		};
+	};
+
 	soc {
 		flash: flash-controller@40022000 {
 			compatible = "st,stm32-flash-controller", "st,stm32g0-flash-controller";