[Buildroot] libungif location has moved

[Andrew Dyer]

I noticed that libungif has moved and a build requiring it will fail
trying to fetch it.  Announcement notice is here:
http://sourceforge.net/forum/forum.php?forum_id=753553

code is currently here:
http://downloads.sourceforge.net/giflib/libungif-4.1.4.tar.bz2

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        The parts of a computer system that can be kicked.