msm: camera: isp: Clean the ISP Blob Cmd processing

Existing handling of generic Blob Cmd includes a couple of function
call jumps and everytime kzalloc + kfree. Cleanup the processing to
avoid these.

Change-Id: I88291a6aa289652ed0f3f4aaee5ae578862a0a1a
Signed-off-by: Harsh Shah <harshs@codeaurora.org>