removed duplicit declaration of prusa_statistics function

Firmware/ultralcd.h

@@ -29,7 +29,6 @@
   void lcd_sdcard_stop();
   void lcd_sdcard_pause();
   void lcd_print_stop();
-  void prusa_statistics(int _message);
   void prusa_statistics(int _message, uint8_t _col_nr = 0);
   void lcd_confirm_print();
   unsigned char lcd_choose_color();