IDE: fix again ruberband with gtk3.

DC logical functions are now disabled when using GTK3.
Apparently using XOR was still having an effect.
Use regular black pen with no logical funciton instead.

[TOPOLOGY]
NetName=None
Nodes=0x01
Node64Present=0x01
Node64Name=micromod
Node64DCFName=PEAK MicroMod.eds
EDSBaseName=eds