Fix bhit/mbhit hitting destroyed objects

A monster zapped a wand of striking, hitting a burning potion
of oil, which destroyed items in the same square, and the ray was
checking destroyed item.  Similar thing with a ray done by hero.

The code currently stops checking the objects in the location
if a next object in the chain was destroyed - an improvement
would be to gather all the objects into an array and iterate
over that instead of relying on the nexthere pointer.

src/zap.c

@@ -2426,6 +2426,8 @@ bhitpile(
                     continue;
             }
         }
+        if (otmp->where != OBJ_FLOOR || otmp->ox != tx || otmp->oy != ty)
+            continue;
         hitanything += (*fhito)(otmp, obj);
     }