i965: Make Broadwell HiZ path arrange for TC flushes.

i965: Make Broadwell HiZ path arrange for TC flushes.

HiZ operations make the depth/render caches out of sync with the sampler
caches.  We need to arrange for a TC flush to happen before the target
buffer is used by the sampler.  Calling brw_render_cache_set_add_bo
makes that happen.

On previous generations, brw_blorp_exec took care of flushing the
texture cache by calling intel_batchbuffer_emit_mi_flush after doing
any rendering.  If we were to use the normal drawing path, then
brw_postdraw_set_buffers_need_resolve would handle this.

On Broadwell, we don't use BLORP, and we don't emit a rectangle
primitive via the normal drawing path.  The 3DSTATE_WM_HZ_OP and
PIPE_CONTROL implicitly make drawing happen.  So, none of our existing
code makes this flush happen - we need to do it directly.

Fixes 11 Piglit copyteximage subtests.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=77223
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=77226
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>