ess go out of sync.

Should that happen, thinkpad-acpi could be really obnoxious when using a
brightness_mode of 3 (both EC and CMOS).  Instead of complaining a massive
number of times, make sure to complain only once until EC and CMOS are back
in sync.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Joerg Platte <lists@naasa.net>
Signed-off-by: Len Brown <len.brown@intel.com>
¿á7v“(x