tty: Convert the USB drivers to the new icount interface

Simple pasting job using the new ops function. Also fix a couple of devices
directly returning the internal struct (which happens at this point to match
for the fields that matter but isn't correct or futureproof)

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

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 97cc87d..891c20e 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -2168,6 +2168,7 @@
 	 * - mask passed in arg for lines of interest
 	 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
 	 * Caller should use TIOCGICOUNT to see which one it was.
+	 * (except that the driver doesn't support it !)
 	 *
 	 * This code is borrowed from linux/drivers/char/serial.c
 	 */