i965: Resolve color for non-coherent FB fetch at UpdateState time.

i965: Resolve color for non-coherent FB fetch at UpdateState time.

This is required because the sampler unit used to fetch from the
framebuffer is unable to interpret non-color-compressed fast-cleared
single-sample texture data.  Roughly the same limitation applies for
surfaces bound to texture or image units, but unlike texture sampling,
non-coherent framebuffer fetch is by definition non-coherent with
previous rendering, so the brw_render_cache_set_check_flush() call can
be omitted except after resolve.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>