usb serial: more fixes and groundwork for tty changes

- If a termios change fails due to lack of memory we should copy the
   old settings back over as the device has not changed
 - Note various locking problems
 - kl5kusb105 had various remaining tty flag handling problems
 - Make safe_serial use tty_insert_flip_string not open coded loops
 - set termios speed properly in usb_serial

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/serial/pl2303.c

@@ -546,6 +546,8 @@ static void pl2303_set_termios(struct usb_serial_port *port,
 	buf = kzalloc(7, GFP_KERNEL);
 	if (!buf) {
 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
+		/* Report back no change occurred */
+		*port->tty->termios = *old_termios;
 		return;
 	}