Move side-effect-free and pure declarations to function definitions

Some Lisp functions still had their `side-effect-free` and `pure`
properties declared in byte-opt.el; do it at their definition instead.
The lists in byte-opt.el now only contain functions implemented in C
and function aliases.

* lisp/emacs-lisp/byte-opt.el (side-effect-free-fns)
(side-effect-and-error-free-fns, pure-fns):
Remove functions whose properties are now declared elsewhere
and some obsolete entries.
* lisp/custom.el (custom-variable-p):
* lisp/emacs-lisp/lisp.el (buffer-end):
* lisp/emacs-lisp/regexp-opt.el (regexp-opt):
* lisp/env.el (getenv):
* lisp/simple.el (count-lines, mark, string-empty-p, lax-plist-get):
* lisp/subr.el (ignore, always, zerop, fixnump, bignump, lsh, last)
(eventp, mouse-movement-p, log10, memory-limit, string-greaterp)
(interactive-p):
* lisp/window.el (get-lru-window, get-largest-window, (window-edges)
(window-body-edges, window-pixel-edges, window-body-pixel-edges)
(window-absolute-pixel-edges, window-absolute-body-pixel-edges)
(one-window-p):
Declare functions `side-effect-free` and/or `pure` as appropriate.

lisp/emacs-lisp/regexp-opt.el

@@ -130,6 +130,7 @@ usually more efficient than that of a simplified version:
      (concat (car parens)
              (mapconcat \\='regexp-quote strings \"\\\\|\")
              (cdr parens))))"
+  (declare (pure t) (side-effect-free t))
   (save-match-data
     ;; Recurse on the sorted list.
     (let* ((max-lisp-eval-depth 10000)