objects: add BUGFIX for OperateSlainHero
The sendmsg parameter is unused in OperateSlainHero, but it should be used in each item creation function to sync the item creation to connected peers.
Compare the OperateSlainHero function to all other OperateFoo functions which take a sendmsg parameter, only OperateSlainHero ignores this parameter. All other functions use it to sync item generation.
There is a decent chance that, had this quest been available in MP, he could have been made to drop a different item for each player.
Lot's of bugs around unsynchronized Quest events, probably why they left them disabled despite initially promising they would be functional by release