fix tests to match ceph osd lost usage

ceph osd lost [--yes-i-really-mean-it]

is now

ceph osd lost <osd-id> [--yes-i-really-mean-it]

http://tracker.ceph.com/issues/5145 refs #5145

Signed-off-by: Loic Dachary <loic@dachary.org>