Don't bind netpolicy right away from batterystats

batteryservice is a 'core' service
netpolicy is an 'other' service

Trying to bind to it straight away fails and leads to a series of
scary Log.wtf messages during boot.

Bug: 72120141
Test: adb logcat -b all
Change-Id: Iad85eaa4b0ec48eb572c22028aca8bd7847fb678