drm/msm/sde: avoid secure-camera/secure-ui concurrency with other displays

Add checks to fail secure-camera/secure-ui updates on
other displays. Fail updates on primary with
secure-camera/secure-ui layers when other display
session is in-progress. This would avoid all the
concurrency during secure updates.

Change-Id: I7cba4d41e3a0c719e18e27689e48d58c16336fa9
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>