Bug 12812: Longoverdue.pl --mark-returned doesn't return items

Bug 12812: Longoverdue.pl --mark-returned doesn't return items

The longoverdue.pl option --mark-returned doesn't work unless the
--charge option is used as well.

Test Plan:
1) Run long overdue with --mark-returned and not --charge,
   note your items are marked lost but not returned
2) Apply this patch
3) Repeat step 1, the items should now get returned!

Tested with (for example):
misc/cronjobs/longoverdue.pl --lost 10=1 --mark-returned --verbose
--confirm

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>