gpio-rcar: Make the platform data gpio_base field signed

The gpio_base field is used to specify the desired GPIO base for the
GPIO controller. The GPIO core can automatically allocate a GPIO number
range when the base is set to -1. To make this possible, make the field
signed.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

include/linux/platform_data/gpio-rcar.h

@@ -17,7 +17,7 @@
 #define __GPIO_RCAR_H__
 
 struct gpio_rcar_config {
-	unsigned int gpio_base;
+	int gpio_base;
 	unsigned int irq_base;
 	unsigned int number_of_pins;
 	const char *pctl_name;