i965/gen7,8: Set SURFACE_IS_ARRAY for all non-3D texture types

i965/gen7,8: Set SURFACE_IS_ARRAY for all non-3D texture types

There's no real reason why we shouldn't set this bit.  It does affect how
the sampler operates a bit but since you can have a 2D non-array view of a
2D_ARRAY texture that distinction is very weak.  Also, this is what ISL
will do and we would like this change to be isolated from using ISL.

Reviewed-by: Chad Versace <chad.versace@intel.com>