lib/unpack.c: improve doxygen description.
lib/unpack.c: improve doxygen description.

--HG--
extra : convert_revision : xtraeme%40gmail.com-20100123051605-ojcxt8uz91hg1h4k

stpx/xbps,datenwolf/xbps,datenwolf/xbps,ebfe/xbps,ebfe/xbps,stpx/xbps,datenwolf/xbps,stpx/xbps,ebfe/xbps