i965: Delete vestiges of resource streamer code.

i965: Delete vestiges of resource streamer code.

We never actually used the resource streamer in any shipping build
of Mesa.  We have no plans to do so in the future.  We looked into
using it in Vulkan, and concluded that it was unusable.  We're not
the only ones to arrive at the conclusion that it's not worth using.

So, drop the last vestiges of resource streamer support and move on.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>