[lmi] Should we update libxml and its kin?

[Greg Chicares]

I pose this question because a corporate-server rebuild says:

+ cd /opt/lmi/src/lmi/third_party/libxslt
+ NOCONFIGURE=1 ./autogen.sh
libtoolize: putting auxiliary files in '.'.
libtoolize: copying file './ltmain.sh'
libtoolize: Consider adding 'AC_CONFIG_MACRO_DIRS([m4])' to configure.ac,
libtoolize: and rerunning libtoolize and aclocal.
libtoolize: Consider adding '-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
configure.ac:123: warning: The macro `AC_HEADER_STDC' is obsolete.
configure.ac:123: You should run autoupdate.
./lib/autoconf/headers.m4:704: AC_HEADER_STDC is expanded from...
configure.ac:123: the top level
configure.ac:12: installing './compile'
[...]
libexslt/Makefile.am: installing './depcomp'
tests/XSLTMark/Makefile.am:420: warning: user target 'html' defined here ...
automake: ... overrides Automake target 'html' defined here
tests/XSLTMark/Makefile.am:420: consider using html-local instead of html

My guess would be that
 - this build is okay, as long as lmi's tests pass;
 - the obvious next step would be to update the relevant
   submodules, in the hope that the xmlsoft.org people
   have already fixed this--in preference to messing
   with their stuff ourselves; and
 - we should probably update all submodules when we
   update wx, which may be soon if the DPI stuff is
   ready for us to test here.
Alternatively, should we add a routine 'autoupdate'
step to every autotoolized rebuild, given that we're
always rebuilding whole libraries from a 'clean' state
and always running 'autogen' anyway?