iio: si1145: Drop GPIO include

The driver include <linux/gpio.h> yet does not use any
of the symbols from the header, so drop the include.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/light/si1145.c

@@ -17,7 +17,6 @@
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
-#include <linux/gpio.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>