msm: mdss: Comply with content protection requirement

Some contents are secure and cannot be displayed on non
secure displays. For example, wireless display can be
non secure and should not display some specific data.
Add a check to ensure protected data does not go to
unsecure wireless display and remains only on primary panel.

Change-Id: If83e21ed66833e648d5d7fad812da56eb5b259c1
CRs-Fixed: 477822
Signed-off-by: Shalabh Jain <shalabhj@codeaurora.org>