msm-core: Ensure the userspace data is copied before access

Userspace data is directly used without copying it to kernel memory.
Ensure all the data reads within ioctl happen from the kernel memory.

Change-Id: I17f6c0c4675e64e121c166b0a062e83a4c5c9757
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>