ssm: Add Secure Service Module driver

Module provides an interface for OEM driver to communicate with Modem
and trustzone

This module provides following features:
- Key-Exchange between Modem and trustzone for encryption/decryption
 of modes information.
- Interface to third party driver to send mode updates to modem.
- Interface for loading the trustzone application.

Change-Id: I5f9cb222378448c61f39b1b437cd4bda7c4f606d
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>
6 files changed