Update for FFmpeg 1.2

flags2 is removed, and the rest of the options hurt more than they help.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
h264enc: be more specific about stream format

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Add missing includes

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
venc: update to avcodec_encode_video2()

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Update to new GLib mutex API

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>