upgrade-0.9: Fail if keyring rewriting misses some keys
upgrade-0.9: Fail if keyring rewriting misses some keys

- Fail during keyring rewriting unless every single keyring entry is
updated; otherwise, we missed a chunk update somewhere

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr