roll-up patch.  change rootfs type to ext4, made appropriate changes to barebox.  found that qtserialport-e v5.1.0 doesn't actually work like we'd expect, added recipe for qtserialport-e v5.2.1 and added preferred version for qtserialport-e to local.conf that we push to the user.  updated sync_and_patch.sh to include the new patch to push that recipe to meta-oe after the fact.