Remove "position" argument from file dialog functions (bug #60980). * libinterp/corefcn/event-manager.cc (F__event_manager_file_dialog__), libinterp/dldfcn/__fltk_uigetfile (F__fltk_uigetfile__): Remove unused argument "position". * scripts/gui/uigetdir.m, scripts/gui/uigetfile.m, scripts/gui/uiputfile.m, scripts/gui/private/__uigetdir_fltk__.m, scripts/gui/private/__uigetfile_fltk__.m, scripts/gui/private/__uiputfile_fltk__.m: Remove handling argument "position".