usb: gadget: net2280: Fix typo on #ifdef

Commit e56e69cc0ff4 ("usb: gadget: net2280: Use pr_* function")
includes a editing mistake on one of the #ifdef.

This patch fixes it.

Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/net2280.c

@@ -1562,7 +1562,7 @@ static const struct usb_gadget_ops net2280_ops = {
 
 /*-------------------------------------------------------------------------*/
 
-#ifdef	CONFIG_USB_GADGET_PDEBUG_FILES
+#ifdef	CONFIG_USB_GADGET_DEBUG_FILES
 
 /* FIXME move these into procfs, and use seq_file.
  * Sysfs _still_ doesn't behave for arbitrarily sized files,