[Tizen] Hard code for va driver

This commit is not upstreamable, check details at
https://codereview.chromium.org/15955009/.

It can be mreged with previous libva patchset
d660a3e Enabling Hardware Acceleration with Libva in linux-x86.
Merge pull request #126 from halton/vaapi-sandbox

Call vaInitialize() at PreSandbox stage.