Update libupnp to 1.6.4.

Changes:
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Version 1.6.4
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2008-01-23 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Workaround for a problem with the new automake AM_CONDITIONAL macro
from autotools-1.10. Thanks to Ingo Hofmann for helping with debugging
this one.

2008-01-22 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Added quoting to macros AC_CONFIG_AUX_DIR, AC_CONFIG_MACRO_DIR and
AC_CONFIG_SRCDIR in configure.ac. Also changed the name of the
auxiliary directory in AC_CONFIG_AUX_DIR to build-aux.

2008-01-22 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Fix for setsockopt() in Threadpool.c to allow more than one process
to join the multicast-group on OSX. Thanks to Ingo Hofmann.

2008-01-22 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Using defined(__OSX__) || defined(__APPLE__) instead of just
defined(__OSX__) in the code. Thanks to Ingo Hofmann and Chris
Pickel.

2008-01-21 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Fix for isFileInVirtualDir. Thanks to Peter Hartley for the patch.

2008-01-07 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* Putting back a "defined(__OSX__)" that has been removed in the
previous *BSD patch. Thanks to Chris Pickel for pointing it out.

2008-01-07 Marcelo Jimenez <mroberto(at)users.sourceforge.net>
* SF Patches Tracker [ 1865812 ] typo in docs comment
Submitted By: Hartmut Holzgraefe - hholzgra
typo in docs comment ACCAPTED instead of ACCEPTED in
@name UPNP_E_UNSUBSCRIBE_UNACCAPTED [-302]
Also, the documentation file name was mispelled and was corrected in
the Makefile.am.

(obache)