system_suspend: remove /sys/power/wake_lock permissions

Now that our tools are routed to system_suspend, there is no reason for
system_suspend to write to /sys/power/wake_[un]lock.

Bug: 128923994
Bug: 115946999
Test: boot blueline, no denials from system_suspend
Change-Id: I1097d30c050ce7d88677e07f4aaef07ce78dc958
1 file changed