Fix mobj unarchiving code
This reverts P_SetMobjSpawnDefaults because it causes various bugs in the mobj unarchiving code, most notably the Cannot remove player mobj by setting its state to S_NULL. error whenever someone joins.
This reverts P_SetMobjSpawnDefaults because it causes various bugs in the mobj unarchiving code, most notably the Cannot remove player mobj by setting its state to S_NULL. error whenever someone joins.