Apply #pragma once, misc cleanup (#12322)

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

Marlin/src/HAL/HAL_LPC1768/include/digipot_mcp4451_I2C_routines.h

@@ -19,13 +19,11 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 // adapted from  I2C/master/master.c example
 //   https://www-users.cs.york.ac.uk/~pcc/MCP/HAPR-Course-web/CMSIS/examples/html/master_8c_source.html
 
-#ifndef _DIGIPOT_MCP4451_I2C_ROUTINES_H_
-#define _DIGIPOT_MCP4451_I2C_ROUTINES_H_
-
 #define USEDI2CDEV_M  1  // use I2C1 controller
 
 #if USEDI2CDEV_M == 0
@@ -53,5 +51,3 @@ uint8_t digipot_mcp4451_send_byte(uint8_t data);
 #ifdef __cplusplus
   }
 #endif
-
-#endif // _DIGIPOT_MCP4451_I2C_ROUTINES_H_