msm: vidc: Add missing qmenu entries for MPEG ctrls

V4l2 control framework mandates a qmenu entry for each control item.
Validate_new() function accesses the qmenu entry for control item,
and any missing qmenu entries causes a crash within this function.
This patch fixes those crashes.

CRs-Fixed: 1031156
Change-Id: Ie507b1de9ce08221678a730146164d6e970aac8a
Signed-off-by: Arun Menon <avmenon@codeaurora.org>
Signed-off-by: Amit Shekhar <ashekhar@codeaurora.org>