Finish reducing of ABL_BILINEAR_SUBDIVISION

Marlin/configuration_store.cpp

 #endif
 
 #if ENABLED(ABL_BILINEAR_SUBDIVISION)
-  extern void bed_level_virt_prepare();
   extern void bed_level_virt_interpolate();
 #endif
 
           EEPROM_READ(bilinear_start);               // 2 ints
           EEPROM_READ(bed_level_grid);               // 9 to 256 floats
           #if ENABLED(ABL_BILINEAR_SUBDIVISION)
-            bed_level_virt_prepare();
             bed_level_virt_interpolate();
           #endif
           //set_bed_leveling_enabled(leveling_is_on);