DB2 restore fails if no DB exists

[Peter Stachowski]

I you create a backup without first having a DB created in DB2, the restore will fail. Here's the error from the guest log:

  ProcessExecutionError: Unexpected error while running command.
  Command: find /home/db2inst1/db2inst1/backup/ -type f -name '*.001' | grep -Po "(?<=backup/)[^.']*(?=\.)"

This seems to be caused by the fact that 'find' returns '1' if it doesn't find anything - this case needs to be handled.