Refactor: libcrmcommon: Replace xmlNewNode() with xmlNewDocRawNode()

Per the libxml2 docs, use of xmlNewNode() is discouraged in favor of
xmlNewDocNode(). Further, entities support is not needed, then
xmlNewDocRawNode() should be used.

https://gnome.pages.gitlab.gnome.org/libxml2/devhelp/libxml2-tree.html#xmlNewNode

Signed-off-by: Reid Wahl <nrwahl@protonmail.com>