tty: Re-add external interface for tty_set_termios()

This is needed by Bluetooth hci_uart module to be able to change speed
of Bluetooth controller and local UART.

Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/tty_ioctl.c

@@ -536,7 +536,7 @@ EXPORT_SYMBOL(tty_termios_hw_change);
  *	Locking: termios_rwsem
  */
 
-static int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
+int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
 {
 	struct ktermios old_termios;
 	struct tty_ldisc *ld;
@@ -569,6 +569,7 @@ static int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
 	up_write(&tty->termios_rwsem);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(tty_set_termios);
 
 /**
  *	set_termios		-	set termios values for a tty

include/linux/tty.h

@@ -491,6 +491,7 @@ static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
 
 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
+extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 
 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
 extern void tty_ldisc_deref(struct tty_ldisc *);