i965: Move CACHE_NEW_SAMPLER to BRW_NEW_SAMPLER_STATE_TABLE.

i965: Move CACHE_NEW_SAMPLER to BRW_NEW_SAMPLER_STATE_TABLE.

This flag signifies that we've emitted a new SAMPLER_STATE table.
Given that we haven't cached those in years, CACHE_NEW_SAMPLER isn't
a great name.  Putting it in the BRW_NEW_* hierarchy would make more
sense; BRW_NEW_SAMPLER_STATE_TABLE better reflects its actual purpose.

When this flag is raised, the pointer to the SAMPLER_STATE table has
changed, so we need to re-issue any packets which point to it (unit
state on Gen4-5, 3DSTATE_SAMPLER_STATE_POINTERS on Gen6, and the
per-stage variants on Gen7+).

Saves 2 * sizeof(void *) bytes per context, as we remove useless
aux_compare/aux_free function pointers.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>