msm: kgsl: Enable Content Protection for A660 GPU

Enable Content Protection feature for A660 GPU. This feature allows
the user to create secure memory and to put the GPU into secure mode.

Change-Id: I3aa0756898446a0876f74654444a9c318307a549
Signed-off-by: Nitheesh Muthuraj <nmuthuraj@codeaurora.org>