leds: tca6507: Include the right header

The TCA6507 optionally presents a GPIO controller, so include
<linux/gpio/driver.h> instead of the legacy <linux/gpio.h>.

Cc: NeilBrown <neilb@suse.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

Author: Linus Walleij

drivers/leds/leds-tca6507.c

@@ -93,7 +93,7 @@
 #include <linux/leds.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
-#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
 #include <linux/workqueue.h>
 #include <linux/leds-tca6507.h>
 #include <linux/of.h>