little glamor cleanups (and a dix cleanup)

[Markus Wick]

Patches 1-5 are:

Reviewed-by: Markus Wick <markus at selfnet.de>

Am 2014-03-06 18:00, schrieb Eric Anholt:
> Here are some trivial patches from the glamor-server branch for
> review.  I'm planning to send out the VBO changes next, which get us
> closer to making glamor not actually suck for performance.
> 
> These are on the glamor-cleanups branch of my tree, branched from
> glamor-pull-request.