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/sierra.c

@@ -566,6 +566,8 @@ static int sierra_chars_in_buffer(struct usb_serial_port *port)
 	 * have sent out, but hasn't made it through to the
 	 * device as we can't see the backend here, so just
 	 * tell the tty layer that everything is flushed.
+	 *
+	 * FIXME: should walk the outstanding urbs info
 	 */
 	return 0;
 }