packaging: install: broken links with DESTDIR
packaging: install: broken links with DESTDIR

Fixed symlinking when DESTDIR is set.
Previously make install created broken symlinks if
DESTDIR was specified.

Change-Id: I1cc1444a5ea4338c73da6026d06055ad19fb943e
Signed-off-by: Sandro Bonazzola <fcb014d63786651910af5db2ecc5316c668188ef@redhat.com>

oVirt/ovirt-iso-uploader,oVirt/ovirt-iso-uploader