Merge from origin/emacs-27

101a049f55 Improve doc string of 'tab-width'.
43c154404e * lisp/emacs-lisp/elp.el: Doc fixes.
1984213f62 * lisp/emacs-lisp/pp.el: Doc fixes.
6486c9dc73 * admin/make-tarball.txt: Note to update more files on web...

diff --cc admin/make-tarball.txt
Simple merge

diff --cc lisp/emacs-lisp/elp.el
Simple merge

diff --cc lisp/emacs-lisp/pp.el
Simple merge

diff --cc src/buffer.c
Simple merge