disp: msm: sde: check new connector state for secure context

During wb use case, if any of the input buffers are secure,
the output buffer must also be in secure. In order to
successfully check if output buffer is secure context,
kernel needs to access new connector state.

Change-Id: Ia0124418eac35cf6d3301603e39ed45b971e2665
Signed-off-by: Nilaan Gunabalachandran <ngunabal@codeaurora.org>