msm: vidc: Remove metadata processing in kernel driver

Part of commit msm: vidc: Remove kernel mapping on input/output buffers

Removed the metadata processing in kerner video driver as kernel
virtual address is removed. The metadata processing can be done
in user space video component

Change-Id: I09c52217817a4a2a9291b5e8f6d515c2dd043756
msm: vidc: Get the current performance level

This change supports client to get the current
performance level of the video driver via
IOCTL_GET_PERF_LEVEL. The current performance
level indicate the number of MBs per second
is being processed by video hardware.

Change-Id: Ic6f5b2b14e0d77bf801c4f857f8a0e20339c199f
Signed-off-by: Maheshwar Ajja <majja@codeaurora.org>
msm: vidc: Initialize kernel space stack variables

This change initializes kernel space stack variables
that are passed between kernel space and user space
using ioctls.
Non initialization of these variables may lead to
leakage of memory values from the kernel stack to
user space.

Change-Id: Icb195470545ee48b55671ac09798610178e833e1
CRs-fixed: 556771,563420
Signed-off-by: Deepak Verma <dverma@codeaurora.org>

Conflicts:

	drivers/video/msm/vidc/common/dec/vdec.c
	drivers/video/msm/vidc/common/enc/venc.c