Fix my mistake with ep sizes with regards to texas mcu footprints
This fixes the ep size as described here https://github.com/KiCad/kicad-footprints/issues/678 for the texas mcu footprints originally added here https://github.com/KiCad/kicad-footprints/pull/587 (the thermal vias version was added in a later pull request it seems)
This also changes the pad shapes to round rect as described here https://github.com/KiCad/kicad-footprints/issues/658