USB: serial: ftdi_sio.c: remove debug module parameter

Now that the dbg() macro is no longer being used in the driver,
the debug module parameter doesn't do anything at all.  So remove
it so as to not confuse people.

CC: Uwe Bonnes <bon@elektron.ikp.physik.tu-darmstadt.de>
CC: Simon Arlott <simon@fire.lp0.eu>
CC: Andrew Worsley <amworsley@gmail.com>
CC: "Michał Wróbel" <michal.wrobel@flytronic.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/ftdi_sio.c

@@ -55,7 +55,6 @@
 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>, Andreas Mohr, Johan Hovold <jhovold@gmail.com>"
 #define DRIVER_DESC "USB FTDI Serial Converters Driver"
 
-static bool debug;
 static __u16 vendor = FTDI_VID;
 static __u16 product;
 
@@ -2431,8 +2430,6 @@ 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");
 module_param(vendor, ushort, 0);
 MODULE_PARM_DESC(vendor, "User specified vendor ID (default="
 		__MODULE_STRING(FTDI_VID)")");