(Hint: reading errno multiple times is incorrect)

Thanks to Ed Schouten for noticing.

I suggest that you actually TEST those fundamental changes BEFORE committing them.

Support for X11 Unichrome and XvMC extensions. The patch includes hw codec and video_output module for testing on VIA boards (CLE266). Patch by Christophe Burgalat <c.burgalat _at_ broadcastavenue _dot_ com>

This patch is not tested yet and is disabled by default.

- Fix threading qualifier warnings