usb/gadget: fix kernel-doc warning

Fix kernel-doc warning, wrong parameter name listed:

Warning(lin2627-g3-kdocfixes//drivers/usb/gadget/config.c:183): No description found for parameter 'match'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/config.c

@@ -168,7 +168,7 @@ usb_copy_descriptors(struct usb_descriptor_header **src)
  * usb_find_endpoint - find a copy of an endpoint descriptor
  * @src: original vector of descriptors
  * @copy: copy of @src
- * @ep: endpoint descriptor found in @src
+ * @match: endpoint descriptor found in @src
  *
  * This returns the copy of the @match descriptor made for @copy.  Its
  * intended use is to help remembering the endpoint descriptor to use