This setting is stored in the EC and available across reboots.

[malattia@linux.it: group function specific variables in a struct, use
kstrtoul]
Signed-off-by: NMarco Chiappero <marco@absence.it>
Signed-off-by: NMattia Dongili <malattia@linux.it>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>