TTY: fix fail path in tty_open

When tty_add_file fails we omit to clean up. Fix that by calling
tty_release appropriatelly.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/tty/tty_io.c

@@ -1894,6 +1894,7 @@ static int tty_open(struct inode *inode, struct file *filp)
 	retval = tty_add_file(tty, filp);
 	if (retval) {
 		tty_unlock();
+		tty_release(inode, filp);
 		return retval;
 	}