Quieten compilation, eg in --without-x builds.

Quieten compilation, eg in --without-x builds.

* lisp/dired-aux.el (lpr-printer-switch):
* lisp/frame.el (tool-bar-height):
* lisp/linum.el (font-info):
* lisp/window.el (font-info, overflow-newline-into-fringe)
(tool-bar-height):
* lisp/emacs-lisp/package-x.el (tar-data-buffer):
* lisp/gnus/gnus-util.el (iswitchb-mode):
* lisp/mail/rmailmm.el (libxml-parse-html-region):
* lisp/net/nsm.el (gnutls-peer-status)
(gnutls-peer-status-warning-describe):
* lisp/net/shr.el (libxml-parse-xml-region):
* lisp/url/url-http.el (gnutls-peer-status): Declare.