msm: vidc: Add support for scaling secure video into non-secure

Under certain conditions, it is acceptable for the decoder to cross
domains and produce non-secure YUVs from a secure bitstream.
This commit adds an interface that allows the client to query the
firmware to read these conditions (i.e. the threshold expressed as
width * height) programmed by TZ under which this operation is allowed.

Change-Id: I5890584ff0c1ac88dc1c4e7c1712b289d3c8f4b3
Signed-off-by: Shalaj Jain <shalajj@codeaurora.org>