Function safe_arch::sub_m128d_s

#[must_use]pub fn sub_m128d_s(a: m128d, b: m128d) -> m128d

This is supported with target feature sse2 only.

Lowest lane a - b, high lane unchanged.

let a = m128d::from_array([92.0, 87.5]);
let b = m128d::from_array([100.0, -600.0]);
let c = sub_m128d_s(a, b).to_array();
assert_eq!(c, [-8.0, 87.5]);