osd/osd_types: add_next_event - add special handler for lost_revert

osd/osd_types: add_next_event - add special handler for lost_revert

For unfound objects, we might append LOST_REVERT log entries,
which shall allow these objects to be reverted to the newest
available version later.
However, we are currently lack of support to rewind the clean_regions
portion too when marking unfound objects as lost with inc-recovery mode
enabled. Hence we must mark these unfound-revert objects as fully dirty
to make sure they can be correctly recovered.

E.g.,:
- primary is pulling object A from replica 1
- object A is corrupted on replica 1
- object A is now unfound
- mark object A as lost, replica 1 will persist a wrong
  missing item for object A..

Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>