I have not run any tests to confirm this, but I believe xml2-config, which you appear to be missing, is installed with libxml2-devel.i686.

Try reinstalling it.
yum reinstall libxml2-devel
You may even want to do a reinstall on each of the libxml2 packages.

Another thing, which I have not tested, is that you may need to install/reinstall kernel-headers and kernel-devel.