driver core: Add missing parameter description to __fwnode_link_add()

The kernel documentation validator is not happy with:

  drivers/base/core.c:67: warning: Function parameter or member 'flags' not described in '__fwnode_link_add'

Add missing parameter description.

Fixes: 6a6dfdf8 ("driver core: fw_devlink: Allow marking a fwnode link as being part of a cycle")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230919195048.3197551-1-andriy.shevchenko@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/core.c

@@ -49,6 +49,7 @@ static bool fw_devlink_best_effort;
  * __fwnode_link_add - Create a link between two fwnode_handles.
  * @con: Consumer end of the link.
  * @sup: Supplier end of the link.
+ * @flags: Link flags.
  *
  * Create a fwnode link between fwnode handles @con and @sup. The fwnode link
  * represents the detail that the firmware lists @sup fwnode as supplying a