ACPI: Use EXPORT_SYMBOL() for acpi_bus_get_device()

Commit caf5c03f (ACPI: Move acpi_bus_get_device() from bus.c to
scan.c) caused acpi_bus_get_device() to be exported using
EXPORT_SYMBOL_GPL(), but that broke some binary drivers in
existence, so revert that change.
Reported-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/scan.c

@@ -968,7 +968,7 @@ int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 	}
 	return 0;
 }
-EXPORT_SYMBOL_GPL(acpi_bus_get_device);
+EXPORT_SYMBOL(acpi_bus_get_device);
 
 int acpi_device_add(struct acpi_device *device,
 		    void (*release)(struct device *))