This was only used for atomic commit these days. So instead just give
atomic it's own work-queue where we can do a block on each bo in turn.
Simplifies things a whole bunch and makes the 'struct fence' conversion
easier.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Better encapsulate the per-timeline stuff into fence-context. For now
there is just a single fence-context, but eventually we'll also have one
per-CRTC to enable fully explicit fencing.
Signed-off-by: Rob Clark <robdclark@gmail.com>