disp: msm: sde: avoid secure display to secure camera transition

During stability tests there are cases where smmu faults are
seen due to direct transition from secure display to secure
camera without smmu ATTACHED state. Added atomic check to avoid
such transitions.

Change-Id: I307e342f35c6e7dab82902fa77e3a5c0c082f4e4
Signed-off-by: Raviteja Tamatam <travitej@codeaurora.org>