* lisp/emacs-lisp/advice.el: Only use defmacro when needed

* lisp/emacs-lisp/advice.el: Only use defmacro when needed

(ad-get-advice-info): Mark it inlinable.
(ad-get-advice-info-macro): Make it an obsolete alias.
(ad-copy-advice-info, ad-is-advised, ad-get-advice-info-field)
(ad-find-advice, ad-macrofy, ad-lambdafy, ad-lambda-p, ad-advice-p)
(ad-compiled-p, ad-compiled-code, ad-get-cache-definition)
(ad-get-cache-id, ad-set-cache): Turn macros into defsubsts.
(ad-defadvice-flags): Make it into a plain list.
(ad-set-advice-info-field): Apply a bit of CSE.