usb: gadget: zero: module parameters can be static

g_zero's module parameters can, and should, be
static. This fixes sparse warnings.

Cc: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/zero.c

@@ -91,17 +91,17 @@ static struct usb_zero_options gzero_options = {
  * functional coverage for the "USBCV" test harness from USB-IF.
  * It's always set if OTG mode is enabled.
  */
-unsigned autoresume = DEFAULT_AUTORESUME;
+static unsigned autoresume = DEFAULT_AUTORESUME;
 module_param(autoresume, uint, S_IRUGO);
 MODULE_PARM_DESC(autoresume, "zero, or seconds before remote wakeup");
 
 /* Maximum Autoresume time */
-unsigned max_autoresume;
+static unsigned max_autoresume;
 module_param(max_autoresume, uint, S_IRUGO);
 MODULE_PARM_DESC(max_autoresume, "maximum seconds before remote wakeup");
 
 /* Interval between two remote wakeups */
-unsigned autoresume_interval_ms;
+static unsigned autoresume_interval_ms;
 module_param(autoresume_interval_ms, uint, S_IRUGO);
 MODULE_PARM_DESC(autoresume_interval_ms,
 		"milliseconds to increase successive wakeup delays");