i965: Don't use CUBE wrap modes for integer formats on IVB/BYT.

i965: Don't use CUBE wrap modes for integer formats on IVB/BYT.

There is no linear filtering for integer formats, so we should always
be using CLAMP_TO_EDGE mode.

Fixes 46 dEQP cases on Ivybridge (which were likely broken by commit
0faf26e6a0a34c3544644852802484f2404cc83e).

This workaround doesn't appear to be necessary on any other hardware;
I haven't found any documentation mentioning errata in this area.

v2: Only apply on Ivybridge/Baytrail to avoid regressing GLES3.1 tests.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net> [v1]