Make exemplaric use of new display charsets in language_en.h and languag_de.h

Marlin/language_de.h

 #define MSG_TEMPERATURE                     "Temperatur"
 #define MSG_MOTION                          "Bewegung"
 #define MSG_VOLUMETRIC                      "Filament"
-#define MSG_VOLUMETRIC_ENABLED		          "E in mm3"
+#define MSG_VOLUMETRIC_ENABLED		          "E in mm" STR_h3
 #define MSG_FILAMENT_SIZE_EXTRUDER_0        "Filament D 1"
 #define MSG_FILAMENT_SIZE_EXTRUDER_1        "Filament D 2"
 #define MSG_FILAMENT_SIZE_EXTRUDER_2        "Filament D 3"

Marlin/language_en.h

 #define MSG_FAN_SPEED                       "Fan speed"
 #define MSG_FLOW                            "Flow"
 #define MSG_CONTROL                         "Control"
-#define MSG_MIN                             " \002 Min"
-#define MSG_MAX                             " \002 Max"
-#define MSG_FACTOR                          " \002 Fact"
+#define MSG_MIN                             " " STR_THERMOMETER " Min"
+#define MSG_MAX                             " " STR_THERMOMETER " Max"
+#define MSG_FACTOR                          " " STR_THERMOMETER " Fact"
 #define MSG_AUTOTEMP                        "Autotemp"
 #define MSG_ON                              "On "
 #define MSG_OFF                             "Off"
 #define MSG_TEMPERATURE                     "Temperature"
 #define MSG_MOTION                          "Motion"
 #define MSG_VOLUMETRIC                      "Filament"
-#define MSG_VOLUMETRIC_ENABLED		        "E in mm3"
+#define MSG_VOLUMETRIC_ENABLED		          "E in mm" STR_h3
 #define MSG_FILAMENT_SIZE_EXTRUDER_0        "Fil. Dia. 1"
 #define MSG_FILAMENT_SIZE_EXTRUDER_1        "Fil. Dia. 2"
 #define MSG_FILAMENT_SIZE_EXTRUDER_2        "Fil. Dia. 3"