platform: msm_shared: Add RPM GLink Client

Glink Client provides api's to drivers that want to
turn on/off regulators and clocks controlled by RPM.
Internally it provides functions to opens channels
to glink, formats request in RPM messaging format
and also provides functions to tear down the connection
before booting to HLOS

Change-Id: I4cddee5c38906a675b07920983a62a7c90a47d90
4 files changed