gpiolib: Group forward declarations in consumer.h

For better maintenance group the forward declarations together.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

include/linux/gpio/consumer.h

@@ -7,6 +7,7 @@
 #include <linux/compiler_types.h>
 #include <linux/err.h>
 
+struct acpi_device;
 struct device;
 struct fwnode_handle;
 struct gpio_desc;
@@ -602,8 +603,6 @@ struct acpi_gpio_mapping {
 	unsigned int quirks;
 };
 
-struct acpi_device;
-
 #if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_ACPI)
 
 int acpi_dev_add_driver_gpios(struct acpi_device *adev,