... for a more relaxed fit of the ground via.
Background: if using a 0.3 mm drill for a finished hole size of 0.2 mm,
the drill to pad edge clearance is only 0.1 mm on the top and bottom of
the pad. To relax the constraints on the manufacturing process, we grow
the pad a little, to add an extra 2 * 0.05 mm of clearance.
The ben-wpan boards were built with the antenna as "trace" (i.e., the
copper is covered with solder mask), but then I adapted the wrong
version of the footprint for kicad-libs.
