Apply #pragma once, misc cleanup (#12322)

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

Marlin/src/feature/dac/stepper_dac.h

@@ -19,31 +19,12 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 /**
  * stepper_dac.h   - To set stepper current via DAC
- *
- * Part of Marlin
- *
- * Copyright (c) 2016 MarlinFirmware
- *
- * Marlin is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * Marlin is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Marlin.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef STEPPER_DAC_H
-#define STEPPER_DAC_H
-
 #include "dac_mcp4728.h"
 
 int dac_init();
@@ -53,5 +34,3 @@ void dac_print_values();
 void dac_commit_eeprom();
 uint8_t dac_current_get_percent(AxisEnum axis);
 void dac_current_set_percents(const uint8_t pct[XYZE]);
-
-#endif // STEPPER_DAC_H