watchdog: pcwd_usb: fix compilation warning

In function ‘usb_pcwd_probe’:
drivers/watchdog/pcwd_usb.c:611:12: warning: variable ‘maxp’ set but not
used [-Wunused-but-set-variable]
  int pipe, maxp;
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/pcwd_usb.c

@@ -608,7 +608,7 @@ static int usb_pcwd_probe(struct usb_interface *interface,
 	struct usb_host_interface *iface_desc;
 	struct usb_endpoint_descriptor *endpoint;
 	struct usb_pcwd_private *usb_pcwd = NULL;
-	int pipe, maxp;
+	int pipe;
 	int retval = -ENOMEM;
 	int got_fw_rev;
 	unsigned char fw_rev_major, fw_rev_minor;
@@ -641,7 +641,6 @@ static int usb_pcwd_probe(struct usb_interface *interface,
 
 	/* get a handle to the interrupt data pipe */
 	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
-	maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 
 	/* allocate memory for our device and initialize it */
 	usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);