drm/i915: Use new bind/unbind in eviction code

Eviction code, like the rest of the converted code needs to be aware of
the address space for which it is evicting (or the everything case, all
addresses). With the updated bind/unbind interfaces of the last patch,
we can now safely move the eviction code over.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>