Make the generalized buffer-local-variable obsolete

Make the generalized buffer-local-variable obsolete

* lisp/paren.el (show-paren-local-mode):
* lisp/electric.el (electric-indent-local-mode)
(electric-layout-local-mode, electric-quote-local-mode):
* lisp/elec-pair.el (electric-pair-local-mode): Don't use it.

* lisp/emacs-lisp/bytecomp.el (byte-compile-warn-obsolete): Autoload.

* lisp/emacs-lisp/gv.el (buffer-local-variable): Make obsolete
(bug#26624).

* lisp/emacs-lisp/gv.el (make-obsolete-generalized-variable): Move
to allow usage.