Apply #pragma once, misc cleanup (#12322)

* Apply #pragma once in headers
* Adjust some thermistors formatting
* Misc cleanup and formatting

Marlin/src/HAL/HAL_ESP32/watchdog_ESP32.h

@@ -19,14 +19,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
-
-#ifndef WATCHDOG_ESP32_H
-#define WATCHDOG_ESP32_H
+#pragma once
 
 // Initialize watchdog with a 4 second interrupt time
 void watchdog_init();
 
 // Reset watchdog.
-inline void watchdog_reset() {};
-
-#endif // WATCHDOG_ESP32_H
+inline void watchdog_reset() { }