charger: Allow to rw /sys/power/[state,wakeup_count]

charger needs to suspend the device when the power goes away
when it doesn't have root. These two files are marked with
group system, user system, mode 0600 in 'on boot', but
it is not executed in charger. Hence, move these actions
to 'on init'.

Test: no failure in libsuspend in charger

Bug: 129138950

Change-Id: I787b935b4ff6177601329aeedccdac361b119ca3
Merged-In: I787b935b4ff6177601329aeedccdac361b119ca3