msm: cvp: optimize CVP HFI packet handling

Remove redundant handling logic. Rename CVP system call
command structure to avoid name conflict with video driver.
Add new commands needed by camera processing pipeline.

Change-Id: I59a628f7ae2bf9ad7c6e075ed3e1a3794f25e05c
Signed-off-by: George Shen <sqiao@codeaurora.org>