Commit 30f9233b36 introduced a test for
Game_Mode, which does not exist, rather than Game_mode, which does
exist. However, the test for game mode is unnecessary. Objects of type
OBJ_NONE are always in segment_none and no object of any other type
should be in segment_none. Use that fact to test obj->type instead of
obj->segnum during multiplayer object clobber, so that multiplayer can
overwrite unallocated objects without accessing any undefined fields and
without making object::segnum a defined field.
Fixes: 30f9233b36 ("Reverted 2e6aa0f081 and partially reverted 7064fcccba to still allow segnum and signature init for multiplayer games, keeping consistency during object sync.")
7ccd537362