gpio: lp873x: Include the right header

This is a driver so include only <linux/gpio/driver.h>.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-lp873x.c

@@ -14,7 +14,7 @@
  * Based on the TPS65218 driver
  */
 
-#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>