Update Italian language (#12951)

Marlin/src/lcd/language/language_it.h

@@ -433,3 +433,10 @@
   #define MSG_FILAMENT_CHANGE_CONT_PURGE_1  _UxGT("Premi x terminare")
   #define MSG_FILAMENT_CHANGE_RESUME_1      _UxGT("Ripresa...")
 #endif // LCD_HEIGHT < 4
+
+#define MSG_TMC_DRIVERS                     _UxGT("Drivers TMC")
+#define MSG_TMC_CURRENT                     _UxGT("Corrente driver")
+#define MSG_TMC_HYBRID_THRS                 _UxGT("Soglia modo ibrido")
+#define MSG_TMC_HOMING_THRS                 _UxGT("Azzer. sensorless")
+#define MSG_TMC_STEPPING_MODE               _UxGT("Modo stepping")
+#define MSG_TMC_STEALTH_ENABLED             _UxGT("StealthChop abil.")