libxml2: fix CVE-2014-0191

libxml2: fix CVE-2014-0191

It was discovered that libxml2, a library providing support to read,
modify and write XML files, incorrectly performs entity substituton in
the doctype prolog, even if the application using libxml2 disabled any
entity substitution. A remote attacker could provide a
specially-crafted XML file that, when processed, would lead to the
exhaustion of CPU and memory resources or file descriptors.

Reference: https://access.redhat.com/security/cve/CVE-2014-0191

(From OE-Core rev: 674bd59d5e357a4aba18c472ac21712a660a84af)

Signed-off-by: Maxin B. John <maxin.john@enea.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>