msm: kgsl: Check snapshot objs size before saving to memory

Before saving the snapshot frozen objects into memory, check
if they fit into snapshot memory size allocated to prevent
out of bound write.

Change-Id: I3f3d3de019eb2b64050b8691af1220f0185aa984
Signed-off-by: Archana Sriram <apsrir@codeaurora.org>