Staging: lustre: obdclass: obd_config: Declare as static

Declare class_add_conn, class_add_profile, class_cleanup,
class_config_parse_rec, class_del_conn, class_detach, class_match_param,
class_attach, class_setup as static since they are used only in this
particular file. Also remove the corresponding declarations from
header files.

Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>