Update to libxml2 2.9.4 by merging commit 'd8083bf7' into klp-dev. am: 312a2fc2f0 am: 7e8d493a9a am: 688b79dd3b  -s ours
am: dcf08c71f8

Change-Id: I41aea5a6bd93aca75e9dbed363792e57cae4fd6d