Function safe_arch::load_replace_high_m128d

#[must_use]pub fn load_replace_high_m128d(a: m128d, b: &f64) -> m128d

This is supported with target feature sse2 only.

Loads the reference into a register, replacing the high lane.

let a = m128d::from([1.0, 2.0]);
let double = 7.0;
let b = load_replace_high_m128d(a, &double);
assert_eq!(b.to_array(), [1.0, 7.0]);