Add a couple kernel-doc lines to prevent warnings.

No functional change.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/f_ecm.c b/drivers/usb/gadget/f_ecm.c
index d893d69..abf8a31 100644
--- a/drivers/usb/gadget/f_ecm.c
+++ b/drivers/usb/gadget/f_ecm.c
@@ -816,6 +816,7 @@
  * @c: the configuration to support the network link
  * @ethaddr: a buffer in which the ethernet address of the host side
  *	side of the link was recorded
+ * @dev: eth_dev structure
  * Context: single threaded during gadget setup
  *
  * Returns zero on success, else negative errno.