Improve dynamic elisp keyword font-locking

Improve dynamic elisp keyword font-locking

* emacs-lisp/byte-run.el (macro-declarations-alist): New
declaration no-font-lock-keyword.
(defmacro): Flush font-lock in existing elisp buffers.

* emacs-lisp/lisp-mode.el (lisp--el-update-after-load)
(lisp--el-update-macro-regexp, lisp--el-macro-regexp): Delete
functions and defconst.
(lisp--el-match-keyword): Rename from lisp--el-match-macro.
(lisp--el-font-lock-flush-elisp-buffers): New function.
(lisp-mode-variables): Remove code for updating
lisp--el-macro-regexp, and add
lisp--el-font-lock-flush-elisp-buffers to after-load-functions.