sftp: Improve check for data subdirs
sftp: Improve check for data subdirs

ar-jan/restic,middelink/restic,jayme-github/restic,jayme-github/restic,ar-jan/restic,kurin/restic,restic/restic,middelink/restic,kurin/restic,fawick/restic,restic/restic,fawick/restic