Provide basic support of H.264 CG for windows x86 build

It is a pure version using ffmpeg to provide basic support of CG for windows although no atrac3+ audio in CG.

Tested with following games and CG runs okay with this commit

1. Project Diva 2 extend
2. Gundam Vs Gundam Next Plus
3. Dragon Ball Z Shin Budokai 2

Courtesy of oioitff and his hard work.