acpi: Add a way to check device status

At present U-Boot does not support the different ACPI status values, but
it is best to put this logic in a central place. Add a function to get the
device status.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

lib/acpi/acpi_device.c

@@ -81,3 +81,8 @@ int acpi_device_scope(const struct udevice *dev, char *scope, int maxlen)
 
 	return 0;
 }
+
+enum acpi_dev_status acpi_device_status(const struct udevice *dev)
+{
+	return ACPI_DSTATUS_ALL_ON;
+}