gfs_controld: GETLK should free unused resource
    
    bz 513285
    
    If a plock resource does not exist in gfs_controld,
    (no posix locks exist on a file), fcntl(GETLK) on that file will
    cause the resource to be created, but not removed afterward.
    
    Signed-off-by: David Teigland <teigland@redhat.com>