Mark BROKEN: fails to build

In file included from plugin.cpp:17:
In file included from ./plugin.h:17:
In file included from ../../ui/esperanza_plugin.h:20:
In file included from ../../lib/xclient.h:21:
In file included from /usr/local/include/xmms2/xmmsclient/xmmsclient++.h:20:
/usr/local/include/xmms2/xmmsclient/xmmsclient++/signal.h:22:10: fatal error: 'boost/function.hpp' file not found
#include <boost/function.hpp>

^~~~~~~~~~~~~~~~~~~~

Reported by: pkg-fallout