msm: mdp: Validate input arguments from user space

Fully verify the input arguments from user client are safe
to use.

Change-Id: Ie14332443b187951009c63ebfb78456dcd9ba60f
Signed-off-by: Raghavendra Ambadas <rambad@codeaurora.org>
Merge "msm: mdp: Validate input arguments from user space"