tty: USB does not need the filp argument in the drivers

And indeed none of them use it. Clean this up as it will make moving to a
standard open method rather easier.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/console.c b/drivers/usb/serial/console.c
index 0e4f2e4..be086e4 100644
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -150,9 +150,9 @@
 		/* only call the device specific open if this
 		 * is the first time the port is opened */
 		if (serial->type->open)
-			retval = serial->type->open(NULL, port, NULL);
+			retval = serial->type->open(NULL, port);
 		else
-			retval = usb_serial_generic_open(NULL, port, NULL);
+			retval = usb_serial_generic_open(NULL, port);
 
 		if (retval) {
 			err("could not open USB console port");