The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the gameport bus code to use the
correct field.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: <linux-input@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>