samples: boards: st: build only this sample for stm32 boards

Makes the sample build only in automatic test CI
Running on the nucleo_f411re board requires hsi enable
Running on the nucleo_wba55cg can still output the console
on the usart1 Tx even if the usart1Rx is used by the MCO output

Signed-off-by: Francois Ramu <[email protected]>

Author: FRASTM

samples/boards/st/mco/boards/nucleo_f411re.overlay

@@ -8,6 +8,11 @@
 	status = "okay";
 };
 
+/* Enable HSI as it will be output on MCO pin by this sample */
+&clk_hsi {
+	status = "okay";
+};
+
 /* see RefMan RM0383 */
 &mco1 {
 	/* Select One of the line below for clock source */

samples/boards/st/mco/boards/nucleo_wba55cg.overlay

@@ -8,17 +8,17 @@
 &clk_lse {
 	status = "okay";
 };
-/* MCO use same pin like usart1 RX - disable usart */
+
 / {
 	chosen {
-		zephyr,bt-c2h-uart = &lpuart1;
-		zephyr,uart-pipe = &lpuart1;
-		zephyr,console = &lpuart1;
-		zephyr,shell-uart = &lpuart1;
+		zephyr,console = &usart1;
+		zephyr,shell-uart = &usart1;
 	};
 };
+
 &usart1 {
-	status = "disabled";
+	/* Do not use the console RX pin : dedicated to the MCO */
+	pinctrl-0 = <&usart1_tx_pb12 &analog_pa8>;
 };
 
 &mco1 {

samples/boards/st/mco/sample.yaml

@@ -2,6 +2,7 @@ sample:
   name: STM32 microcontroller clock output (MCO) example
 tests:
   sample.board.stm32.mco:
+    build_only: true
     platform_allow:
       - nucleo_f411re
       - nucleo_f446ze