i965: Force X-tiling for 128 bpp formats on Sandybridge.

i965: Force X-tiling for 128 bpp formats on Sandybridge.

128 bpp formats are not allowed to be Y-tiled on any architectures
except Gen7.

+11 Piglits on Sandybridge (mostly regression fixes since the
switch to Y-tiling).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=63867
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64261
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Chad Versace <chad.versace@linux.intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Cc: "9.2" <mesa-stable@lists.freedesktop.org>