The merge functions duplicate entries as needed and they don't free
them. Release them in unpack_nondirectories, the same function
where they were allocated, after we're done.
As suggested by Felipe, use the same loop style (zero-based for loop)
for freeing as for allocating.
Improved-by: Felipe Contreras <felipe.contreras@gmail.com> Signed-off-by: René Scharfe <rene.scharfe@lsrfire.ath.cx> Signed-off-by: Junio C Hamano <gitster@pobox.com>