Update emacs-w3m to version 1.4.632+512+gc3a3a947 / rev 6 via SR 969236
    
    https://build.opensuse.org/request/show/969236
    by user AndreasSchwab + dimstar_suse
    - Update to version 1.4.632+512+gc3a3a947:
      * * Makefile.in (configure): Replace configure.in with configure.ac
      * Make the builder work for autoconf 2.70 and up as well
      * Drop Emacs 26 support
      * * shimbun/ChangeLog: Remove cancelled entry
      * * sb-kyoko-np.el (shimbun-clear-contents): Revert
      * * sb-kyoko-np.el (shimbun-clear-contents): Make date header precision
      * * mime-w3m.el: Fix last change
      * Typo fix
      * Conceal warnings for the case SEMI is absent (issue #108)
      * * sb-sankei.el (w3m-cookie-setup): Autoload it
      * * w3m.el (w3m-image-type-alist): Update docstring (forwarded request 969234 from AndreasSchwab)