gpio: xilinx: Use the right include

This is a GPIO driver so use only <linux/gpio/driver.h>.
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-xilinx.c

@@ -20,7 +20,7 @@
 #include <linux/of_platform.h>
 #include <linux/of_gpio.h>
 #include <linux/io.h>
-#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
 #include <linux/slab.h>
 
 /* Register Offset Definitions */