msm: camera2: cpp: Added secure buffer [un]mapping

The CPP HW needs to use secured SMMU access APIs for
supporting secured sessions

CRs-fixed: 1060631

Change-Id: I814c4b219c0c3b91c4e1280b09c2b819d864f787
Signed-off-by: Ravi kumar Koyyana <rkoyyana@codeaurora.org>