USB: Serial: mos7720.c: remove debug module parameter

Now that all usb-serial modules are only using dev_dbg()
the debug module parameter does not do anything at all, so
remove it to reduce any confusion if someone were to try to
use it.

CC: Johan Hovold <jhovold@gmail.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/mos7720.c

@@ -71,8 +71,6 @@ struct moschip_port {
 	struct urb		*write_urb_pool[NUM_URBS];
 };
 
-static bool debug;
-
 static struct usb_serial_driver moschip7720_2port_driver;
 
 #define USB_VENDOR_ID_MOSCHIP		0x9710
@@ -2133,6 +2131,3 @@ module_usb_serial_driver(serial_drivers, id_table);
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
-
-module_param(debug, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(debug, "Debug enabled or not");