Update p5-XML-LibXML to 2.0123:

2.0123  2015-12-06
    - Get rid of an undef-warning in XML::LibXML::Reader .
        - https://rt.cpan.org/Ticket/Display.html?id=106830
        - Thanks to Rich for the report and testcase.
    - Apply patch from Debian for rewording the documentation.
        - https://rt.cpan.org/Ticket/Display.html?id=110116
        - Some extra rewording has been done by SHLOMIF.
        - Thanks to Gregor Herrman and the Debian Team

(wiz)