rlogind: don't call forkpty()
    
    We can no longer call forkpty (a convenience routine that combines
    openpty, fork, and login_tty) because, with forkpty, the slave end of
    the pty is open only in the child process. The child process execs
    /bin/login which now closes all open file descriptors before doing
    a vhangup (see lkml.org/lkml/2012/6/5/145), and this resets packet
    mode on the pty, undoing the effect of the ioctl(master, TIOCPKT,
    &on) call made by the parent.
    
    Instead, we call openpty, fork, and login_tty individually, so
    that we can keep a file descriptor to the slave open in the parent
    process, thereby retaining packet mode even when the child closes
    file descriptors to call vhangup.
    
    Patch contributed by Philip Spencer, <pspencer@fields.utoronto.ca>.
    
    Resolves RHBZ #947213.
    
    Signed-off-by: Michal Sekletar <msekleta@redhat.com>