[Fixed for V0.42] DM fireball launcher in void

[Lunever]

I didn't have much time so far for V0.41 - yet I noticed 1 minor issue:

When I originally reported, that the monsters in the DM1 delta antechamber in the void level did not trigger any fireballs anymore, you misunderstood me at first by assuming that they are producing to few fireballs and tried to correct it by adding additional floor triggers. However, there were not to few, there were no fireballs at all: that problems was fixed along with other floor trigger issues, yet the additional floorpads are still in there and now that the real bug is fixed they produce just too much fireballs. Please remove them again in order to restore the properly working original state.

[George Gilbert]

Done for V0.42