Lower correctness threshold for 32-bit builds
Lower correctness threshold for 32-bit builds

The scalar version of the code produces quite different results in
32-bit.


Former-commit-id: 45f18a58ec4d12db60cfe00a4341de7cfb08ffbc
darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide