TTY: ircomm: fix DTR being raised on hang up

Make sure to check ASYNC_INITIALISED before raising DTR when waking up
from blocked open in ircomm_tty_block_til_ready.

Currently DTR could get raised at hang up as a blocked process would
raise DTR unconditionally before checking for hang up and returning.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/irda/ircomm/ircomm_tty.c

@@ -328,7 +328,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
 	spin_unlock_irqrestore(&port->lock, flags);
 
 	while (1) {
-		if (tty->termios.c_cflag & CBAUD)
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 
 		set_current_state(TASK_INTERRUPTIBLE);