msm: venc: Initialize all encoder V4L2 custom control to proper type

If control type is not initialized properly, there can be a chance
default garbage values make custom control type as private.
Initialize all encoder V4L2 custom control type with proper type.

CRs-Fixed: 550808
Change-Id: If912526772a5b807fc72cf78e54f23ac16846f0b
Signed-off-by: Srinu Gorle <sgorle@codeaurora.org>