This patch registers NS memory buffer with the secure payload using
two different functions IDs - REGISTER_LOGBUF, REGISTER_REQBUF.

a. The SP uses the log-buffer to store its activity logs, in a
pre-decided format. This helps in debugging secure payload's issues.
b. The SP uses the req-buffer to get the parameters required by
sessions with Trusted Applications.

Change-Id: I6b0247cf7790524132ee0da24f1f35b1fccec5d5
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>