Apply #pragma once, misc cleanup (#12322)

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

Marlin/src/lcd/language/language_pt-br.h

@@ -19,6 +19,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#pragma once
 
 /**
  * Portuguese (Brazil)
@@ -28,8 +29,6 @@
  * See also http://marlinfw.org/docs/development/lcd_language.html
  *
  */
-#ifndef LANGUAGE_PT_BR_UTF_H
-#define LANGUAGE_PT_BR_UTF_H
 
 // Put characters here that should be displayed with M117
 //_UxGT("áãàçÉéêíóõ")
@@ -382,5 +381,3 @@
   #define MSG_FILAMENT_CHANGE_EXTRUDE_1     _UxGT("Extrusando...")
   #define MSG_FILAMENT_CHANGE_RESUME_1      _UxGT("Continuando...")
 #endif
-
-#endif // LANGUAGE_PT_BR_UTF_H