Fix initial UI state of battery protection setting
requested to merge timjagenberg/powerdevil:bugfix/488954-battery-protection-initial-state into master
The setting 'Battery protection' in System Settings -> Power Management
-> Advanced Power Settings was always initially shown deactivatet and
did not reflect the actualy state of the system as given in
/sys/bus/platform/drivers/ideapad_acpi/VPC2004\:00/conservation_mode.
This was fixed so that the initial GUI state reflects the current system
state.