pinctrl: Add void * to pinctrl_pin_desc

drv_data is added to the pinctrl_pin_desc for drivers to define additional
driver-specific per-pin data.
Signed-off-by: Sherman Yin <syin@broadcom.com>
Reviewed-by: Christian Daudt <bcm@fixthebug.org>
Reviewed-by: Matt Porter <matt.porter@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

include/linux/pinctrl/pinctrl.h

@@ -32,10 +32,12 @@ struct device_node;
  * pins, pads or other muxable units in this struct
  * @number: unique pin number from the global pin number space
  * @name: a name for this pin
+ * @drv_data: driver-defined per-pin data. pinctrl core does not touch this
  */
 struct pinctrl_pin_desc {
 	unsigned number;
 	const char *name;
+	void *drv_data;
 };
 
 /* Convenience macro to define a single named or anonymous pin descriptor */