As the backlight device registered by fujitsu-laptop relies on the
FUJ02B1 ACPI device being present, only register the backlight device
once that ACPI device is detected.
Suggested-by: NAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: NMichał Kępień <kernel@kempniu.pl>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-and-tested-by: NJonathan Woithe <jwoithe@just42.net>