Add WHEN arg to make-obsolete calls
Convert TeX-auto-add-type to a macro.

* tex.el (TeX-auto-add-type): Convert to macro.

* lpath.el: Don't silence byte-compiler.

* latex.el (LaTeX-auto-style, LaTeX-auto-arguments)
(LaTeX-auto-optional, LaTeX-auto-env-args): Defvar explicitly
before use.