boards: stm32h747i_disco: Minor fixes

* Exlude _m4target from net tests as they assume SERIAL is enabled,
which is not the case (yet).
Fixes: #19065
* Zephyr drivers headers were moved from include/ to include/drivers.
Update pinmux.h path to the new location.
* Add missing status line on joystick_left dts node.

Signed-off-by: Erwan Gouriou <erwan.gouriou@linaro.org>

boards/arm/stm32h747i_disco/pinmux.c

@@ -7,7 +7,7 @@
 #include <kernel.h>
 #include <device.h>
 #include <init.h>
-#include <pinmux.h>
+#include <drivers/pinmux.h>
 #include <sys_io.h>
 
 #include <pinmux/stm32/pinmux_stm32.h>

boards/arm/stm32h747i_disco/stm32h747i_disco.dtsi

@@ -54,6 +54,7 @@
 		joy_left: joystick_left {
 			label = "joystick left";
 			gpios = <&gpiok 4 GPIO_INT_ACTIVE_LOW>;
+			status = "disabled";
 		};
 		joy_right: joystick_right {
 			label = "joystick right";

boards/arm/stm32h747i_disco/stm32h747i_disco_m4.yaml

@@ -14,3 +14,4 @@ testing:
   ignore_tags:
     - mpu
     - nfc
+    - net