message: Remove non-power-of-two SIMD vectors
diff: @@ -7,10 +7,6 @@ struct i32x2(i32, i32);
  #[repr(simd)]
  #[derive(Copy, Clone, Debug, PartialEq)]
  #[allow(non_camel_case_types)]
  -struct i32x3(i32, i32, i32);
  -#[repr(simd)]
  -#[derive(Copy, Clone, Debug, PartialEq)]
  -#[allow(non_camel_case_types)]
  struct i32x4(i32, i32, i32, i32);
  #[repr(simd)]
  #[derive(Copy, Clone, Debug, PartialEq)]
  @@ -20,12 +16,10 @@ struct i32x8(i32, i32, i32, i32,
  fn main() {
  let _x2 = i32x2(20, 21);
  - let _x3 = i32x3(30, 31, 32);
  let _x4 = i32x4(40, 41, 42, 43);
  let _x8 = i32x8(80, 81, 82, 83, 84, 85, 86, 87);
  let _y2 = i32x2(120, 121);
  - let _y3 = i32x3(130, 131, 132);
  let _y4 = i32x4(140, 141, 142, 143);
  let _y8 = i32x8(180, 181, 182, 183, 184, 185, 186, 187);
  