ants/ants.brd: add exclusion zone around ground pad on top layer
ants/ants.brd: add exclusion zone around ground pad on top layer

cfriedt/ben-wpan,cfriedt/ben-wpan,cfriedt/ben-wpan,cfriedt/ben-wpan,cfriedt/ben-wpan,cfriedt/ben-wpan