Implement equality operator for #[simd] types

[brendanzab]

#![feature(simd)]
#![allow(experimental)]

use std::unstable::simd::i32x4;

fn main() {
    let x = i32x4(1, 2, 3, 4);
    let y = i32x4(1, 2, 3, 4);
    let _ = x == y;
}

simd-asm-test.rs:9:13: 9:19 error: internal compiler error: non-scalar comparison
simd-asm-test.rs:9     let _ = x == y;
                               ^~~~~~
note: the compiler hit an unexpected failure path. this is a bug.
note: we would appreciate a bug report: http://static.rust-lang.org/doc/master/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace

[Ryman]

This works on master and has tests.

#![feature(simd)]
#![allow(experimental)]

use std::simd::i32x4;

fn main() {
    let x = i32x4(1, 2, 3, 4);
    let y = i32x4(7, 2, 3, 4);
    let _ = x == y;
    println!("{}", x == y);
}

Tests are here

Can this be closed?