- fixed uninitialized ObjectList.

This needs to clear each entry each time it is allocated for use.
The object where this frequently caused problems is the drum being spawned by the Anubis drummers.

source/games/exhumed/src/object.cpp

@@ -1964,6 +1964,7 @@ int BuildObject(int const nSprite, int nOjectType, int nHitag)
     auto spr = &sprite[nSprite];
 
     auto nObject = ObjectList.Reserve(1);
+    ObjectList[nObject] = {};
 
     changespritestat(nSprite, ObjectStatnum[nOjectType]);