Duplicated origin for libxml2-2.9.10: textproc/py-libxml2 AND textproc/libxml2

[Yuri]

After some recent commit some ports now fail in poudriere:

[00:00:09] Warning: (textproc/py-libxml2): Error: Duplicated origin for 
libxml2-2.9.10: textproc/py-libxml2 AND textproc/libxml2. Rerun with -v 
to see which ports are depending on these.
[00:00:09] Error: Fatal errors encountered gathering ports metadata

For example cad/ktechlab fails.


Yuri