m8: Fix VoIP clients

From xda user @dante020

This fixes no sound coming from the earpiece during a call
(tested with Google Voice). This issue can be reproduced on
all SIP clients such as CSipSimple, Media5 Fone, Bria,
Skype, as well as the built-in CM dialer SIP client.

Change-Id: Ia1f8a11893b14d3a419b8dcd88818084cc1b024a
m8: update power configuration

Use CAF recommended settings and enable low power modes

Change-Id: Id67cd206d98dbb9a10d2da6aaa7766550b71efc9