fix the error when a monster's oid in map equals charId, (the item will drop from the error monster) (#400)
fix the error when a monster's oid in map equals charId, (the item will drop from the error monster) (#400)

(cherry picked from commit 5c1017c73d83b7bc646c36bdde2d7904af78a111)
ronancpl/MapleSolaxiaV2,ronancpl/MapleSolaxiaV2