Fix volumetric multiplier display for filament sensor (PR#2264)

The volumetric multiplier display needs to be multiplied by 100 in order to make it an integer for display purposes.

Marlin/dogm_lcd_implementation.h

       lcd_printPGM(PSTR("dia:"));
       lcd_print(ftostr12ns(filament_width_meas));
       lcd_printPGM(PSTR(" factor:"));
-      lcd_print(itostr3(volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]));
+      lcd_print(itostr3(100.0 * volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]));
       lcd_print('%');
     }
   #endif