ncurses 6.4 - patch 20231118

ncurses 6.4 - patch 20231118

+ improve description of length-parameter and error-returns in several
  manpages:  curs_addchstr.3x, curs_addstr.3x, curs_addwstr.3x,
  curs_in_wch.3x, curs_in_wchstr.3x, curs_inchstr.3x, curs_ins_wstr.3x,
  curs_insstr.3x, curs_instr.3x, curs_inwstr.3x
+ amend parameter check for entire string versus specific length in
  winsnstr() and wins_nwstr() to match Solaris.
+ make similar correction to wins_nwstr().
+ correct loop termination condition in waddnstr() and waddnwstr()
  (Debian #1055882, cf: 20201205).