Upgrade to 21.5 beta20 "cilantro" with help from xemacs-devel-mule upgrade
by Andrey Slusar. The same patch-configure.ac is used. Changes in patches
patch-mem-limits.h and patch-emacs.c are solved, but a bit differently in
source so remove them. Autoconf 2.59 is changed which changes a few
configure options names.
Security: Fixes VuXML 3e3c860d-7dae-11d9-a9e7-0001020eed82