serial: mxs-auart: Fix mxs_auart_set_ldisc()

Commit 732a84a037 ("serial: core: Pass termios to set_ldisc() notifications")
changed the set_ldisc prototype.

At the time of this commit the mxs_auart driver did not implement set_ldisc,
so that's why it has not been converted.

Adapt also mxs_auart_set_ldisc() so that the following build warning can be
fixed:

drivers/tty/serial/mxs-auart.c:962:2: warning: initialization from
incompatible pointer type
  .set_ldisc      = mxs_auart_set_ldisc,
  ^
drivers/tty/serial/mxs-auart.c:962:2: warning: (near initialization
for 'mxs_auart_ops.set_ldisc')

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/mxs-auart.c

@@ -784,9 +784,10 @@ static void mxs_auart_settermios(struct uart_port *u,
 		mxs_auart_disable_ms(u);
 }
 
-static void mxs_auart_set_ldisc(struct uart_port *port, int new)
+static void mxs_auart_set_ldisc(struct uart_port *port,
+				struct ktermios *termios)
 {
-	if (new == N_PPS) {
+	if (termios->c_line == N_PPS) {
 		port->flags |= UPF_HARDPPS_CD;
 		mxs_auart_enable_ms(port);
 	} else {