ipcalc: fix a double slash for IPv6 in olsr_ip_prefix_to_string
ipcalc: fix a double slash for IPv6 in olsr_ip_prefix_to_string

Signed-off-by: Ferry Huberts <66e11f9f5d965b69497c7e73d5e808f8b13c1218@pelagic.nl>

diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap,diogomg/olsrd-binary-heap