Implement VP8 temporal layer encode in libmix

BZ: 165682

Implement VP8 temporal layer encode in libmix
Fix some code style issues;
Fix data structure overflow issue.

Change-Id: I14958416381597c4b47b74a6cd99d83880028b29
Signed-off-by: liubolun <bolun.liu@intel.com>
5 files changed