siox: Add helper macro to simplify driver registration

Add more helper macros for trivial driver init cases, similar to the
already existing module_platform_driver() or module_i2c_driver().

This helps to reduce driver init boilerplate.
Signed-off-by: Enrico Weigelt <info@metux.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

include/linux/siox.h

@@ -75,3 +75,13 @@ static inline void siox_driver_unregister(struct siox_driver *sdriver)
 {
 	return driver_unregister(&sdriver->driver);
 }
+
+/*
+ * module_siox_driver() - Helper macro for drivers that don't do
+ * anything special in module init/exit.  This eliminates a lot of
+ * boilerplate.  Each module may only use this macro once, and
+ * calling it replaces module_init() and module_exit()
+ */
+#define module_siox_driver(__siox_driver) \
+	module_driver(__siox_driver, siox_driver_register, \
+			siox_driver_unregister)